diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6234b8ba..94aa4575 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,7 +13,7 @@
   enabled, causes the Karapace schema-registry service to shutdown when there are invalid schema records
   in the `_schemas` topic
 - Add `Kafka` field `userConfig.single_zone`, type `object`: Single-zone configuration
-- Change `Kafka` field `userConfig.kafka_version`: enum ~~`[3.4, 3.5, 3.6, 3.7]`~~ → `[3.5, 3.6, 3.7, 3.8]`
+- Change `Kafka` field `userConfig.kafka_version`: enum remove `3.5`, `3.6`
 - Add `MySQL` field `userConfig.mysql.log_output`, type `string`: The slow log output destination when
   slow_query_log is ON
 - Add `OpenSearch` field `userConfig.azure_migration.indices`, type `string`: A comma-delimited list
@@ -49,6 +49,8 @@
   minimum ~~`1`~~ → `0`
 - Change `OpenSearch` field `userConfig.opensearch.auth_failure_listeners.ip_rate_limiting.time_window_seconds`:
   minimum ~~`1`~~ → `0`
+- Change `Cassandra` field `userConfig.cassandra_version`: enum remove `4`
+- Change `PostgreSQL` field `userConfig.pg_version`: enum remove `12`
 
 ## v0.25.0 - 2024-09-19
 
diff --git a/api/v1alpha1/userconfig/service/cassandra/cassandra.go b/api/v1alpha1/userconfig/service/cassandra/cassandra.go
index 111bc981..c9a71c59 100644
--- a/api/v1alpha1/userconfig/service/cassandra/cassandra.go
+++ b/api/v1alpha1/userconfig/service/cassandra/cassandra.go
@@ -71,7 +71,7 @@ type CassandraUserConfig struct {
 	Cassandra *Cassandra `groups:"create,update" json:"cassandra,omitempty"`
 
 	// +kubebuilder:validation:Pattern=`^[0-9]+(\.[0-9]+)?$`
-	// +kubebuilder:validation:Enum="4";"4.1"
+	// +kubebuilder:validation:Enum="4.1"
 	// Cassandra version
 	CassandraVersion *string `groups:"create,update" json:"cassandra_version,omitempty"`
 
diff --git a/api/v1alpha1/userconfig/service/kafka/kafka.go b/api/v1alpha1/userconfig/service/kafka/kafka.go
index 5a3f575b..ecc79660 100644
--- a/api/v1alpha1/userconfig/service/kafka/kafka.go
+++ b/api/v1alpha1/userconfig/service/kafka/kafka.go
@@ -576,7 +576,7 @@ type KafkaUserConfig struct {
 	// Kafka SASL mechanisms
 	KafkaSaslMechanisms *KafkaSaslMechanisms `groups:"create,update" json:"kafka_sasl_mechanisms,omitempty"`
 
-	// +kubebuilder:validation:Enum="3.5";"3.6";"3.7";"3.8"
+	// +kubebuilder:validation:Enum="3.7";"3.8"
 	// Kafka major version
 	KafkaVersion *string `groups:"create,update" json:"kafka_version,omitempty"`
 
diff --git a/api/v1alpha1/userconfig/service/pg/pg.go b/api/v1alpha1/userconfig/service/pg/pg.go
index d28c0c0a..c5ddf102 100644
--- a/api/v1alpha1/userconfig/service/pg/pg.go
+++ b/api/v1alpha1/userconfig/service/pg/pg.go
@@ -533,7 +533,7 @@ type PgUserConfig struct {
 	// Enable the pg_stat_monitor extension. Enabling this extension will cause the cluster to be restarted.When this extension is enabled, pg_stat_statements results for utility commands are unreliable
 	PgStatMonitorEnable *bool `groups:"create,update" json:"pg_stat_monitor_enable,omitempty"`
 
-	// +kubebuilder:validation:Enum="12";"13";"14";"15";"16"
+	// +kubebuilder:validation:Enum="13";"14";"15";"16"
 	// PostgreSQL major version
 	PgVersion *string `groups:"create,update" json:"pg_version,omitempty"`
 
diff --git a/charts/aiven-operator-crds/templates/aiven.io_cassandras.yaml b/charts/aiven-operator-crds/templates/aiven.io_cassandras.yaml
index 4f7a9d3e..a34b88b3 100644
--- a/charts/aiven-operator-crds/templates/aiven.io_cassandras.yaml
+++ b/charts/aiven-operator-crds/templates/aiven.io_cassandras.yaml
@@ -290,7 +290,6 @@ spec:
                     cassandra_version:
                       description: Cassandra version
                       enum:
-                        - "4"
                         - "4.1"
                       pattern: ^[0-9]+(\.[0-9]+)?$
                       type: string
diff --git a/charts/aiven-operator-crds/templates/aiven.io_kafkas.yaml b/charts/aiven-operator-crds/templates/aiven.io_kafkas.yaml
index eca5e9d7..b3085ba5 100644
--- a/charts/aiven-operator-crds/templates/aiven.io_kafkas.yaml
+++ b/charts/aiven-operator-crds/templates/aiven.io_kafkas.yaml
@@ -1000,8 +1000,6 @@ spec:
                     kafka_version:
                       description: Kafka major version
                       enum:
-                        - "3.5"
-                        - "3.6"
                         - "3.7"
                         - "3.8"
                       type: string
diff --git a/charts/aiven-operator-crds/templates/aiven.io_postgresqls.yaml b/charts/aiven-operator-crds/templates/aiven.io_postgresqls.yaml
index 0756a45c..40bac237 100644
--- a/charts/aiven-operator-crds/templates/aiven.io_postgresqls.yaml
+++ b/charts/aiven-operator-crds/templates/aiven.io_postgresqls.yaml
@@ -777,7 +777,6 @@ spec:
                     pg_version:
                       description: PostgreSQL major version
                       enum:
-                        - "12"
                         - "13"
                         - "14"
                         - "15"
diff --git a/config/crd/bases/aiven.io_cassandras.yaml b/config/crd/bases/aiven.io_cassandras.yaml
index 4f7a9d3e..a34b88b3 100644
--- a/config/crd/bases/aiven.io_cassandras.yaml
+++ b/config/crd/bases/aiven.io_cassandras.yaml
@@ -290,7 +290,6 @@ spec:
                     cassandra_version:
                       description: Cassandra version
                       enum:
-                        - "4"
                         - "4.1"
                       pattern: ^[0-9]+(\.[0-9]+)?$
                       type: string
diff --git a/config/crd/bases/aiven.io_kafkas.yaml b/config/crd/bases/aiven.io_kafkas.yaml
index eca5e9d7..b3085ba5 100644
--- a/config/crd/bases/aiven.io_kafkas.yaml
+++ b/config/crd/bases/aiven.io_kafkas.yaml
@@ -1000,8 +1000,6 @@ spec:
                     kafka_version:
                       description: Kafka major version
                       enum:
-                        - "3.5"
-                        - "3.6"
                         - "3.7"
                         - "3.8"
                       type: string
diff --git a/config/crd/bases/aiven.io_postgresqls.yaml b/config/crd/bases/aiven.io_postgresqls.yaml
index 0756a45c..40bac237 100644
--- a/config/crd/bases/aiven.io_postgresqls.yaml
+++ b/config/crd/bases/aiven.io_postgresqls.yaml
@@ -777,7 +777,6 @@ spec:
                     pg_version:
                       description: PostgreSQL major version
                       enum:
-                        - "12"
                         - "13"
                         - "14"
                         - "15"
diff --git a/docs/docs/api-reference/cassandra.md b/docs/docs/api-reference/cassandra.md
index 4916532f..7131467c 100644
--- a/docs/docs/api-reference/cassandra.md
+++ b/docs/docs/api-reference/cassandra.md
@@ -207,7 +207,7 @@ Cassandra specific user configuration options.
 - [`backup_hour`](#spec.userConfig.backup_hour-property){: name='spec.userConfig.backup_hour-property'} (integer, Minimum: 0, Maximum: 23). The hour of day (in UTC) when backup for the service is started. New backup is only started if previous backup has already completed.
 - [`backup_minute`](#spec.userConfig.backup_minute-property){: name='spec.userConfig.backup_minute-property'} (integer, Minimum: 0, Maximum: 59). The minute of an hour when backup for the service is started. New backup is only started if previous backup has already completed.
 - [`cassandra`](#spec.userConfig.cassandra-property){: name='spec.userConfig.cassandra-property'} (object). cassandra configuration values. See below for [nested schema](#spec.userConfig.cassandra).
-- [`cassandra_version`](#spec.userConfig.cassandra_version-property){: name='spec.userConfig.cassandra_version-property'} (string, Enum: `4`, `4.1`, Pattern: `^[0-9]+(\.[0-9]+)?$`). Cassandra version.
+- [`cassandra_version`](#spec.userConfig.cassandra_version-property){: name='spec.userConfig.cassandra_version-property'} (string, Enum: `4.1`, Pattern: `^[0-9]+(\.[0-9]+)?$`). Cassandra version.
 - [`ip_filter`](#spec.userConfig.ip_filter-property){: name='spec.userConfig.ip_filter-property'} (array of objects, MaxItems: 1024). Allow incoming connections from CIDR address block, e.g. `10.20.0.0/16`. See below for [nested schema](#spec.userConfig.ip_filter).
 - [`migrate_sstableloader`](#spec.userConfig.migrate_sstableloader-property){: name='spec.userConfig.migrate_sstableloader-property'} (boolean). Sets the service into migration mode enabling the sstableloader utility to be used to upload Cassandra data files. Available only on service create.
 - [`private_access`](#spec.userConfig.private_access-property){: name='spec.userConfig.private_access-property'} (object). Allow access to selected service ports from private networks. See below for [nested schema](#spec.userConfig.private_access).
diff --git a/docs/docs/api-reference/kafka.md b/docs/docs/api-reference/kafka.md
index d2fed93b..9fc8b361 100644
--- a/docs/docs/api-reference/kafka.md
+++ b/docs/docs/api-reference/kafka.md
@@ -217,7 +217,7 @@ Kafka specific user configuration options.
 - [`kafka_rest_authorization`](#spec.userConfig.kafka_rest_authorization-property){: name='spec.userConfig.kafka_rest_authorization-property'} (boolean). Enable authorization in Kafka-REST service.
 - [`kafka_rest_config`](#spec.userConfig.kafka_rest_config-property){: name='spec.userConfig.kafka_rest_config-property'} (object). Kafka REST configuration. See below for [nested schema](#spec.userConfig.kafka_rest_config).
 - [`kafka_sasl_mechanisms`](#spec.userConfig.kafka_sasl_mechanisms-property){: name='spec.userConfig.kafka_sasl_mechanisms-property'} (object). Kafka SASL mechanisms. See below for [nested schema](#spec.userConfig.kafka_sasl_mechanisms).
-- [`kafka_version`](#spec.userConfig.kafka_version-property){: name='spec.userConfig.kafka_version-property'} (string, Enum: `3.5`, `3.6`, `3.7`, `3.8`). Kafka major version.
+- [`kafka_version`](#spec.userConfig.kafka_version-property){: name='spec.userConfig.kafka_version-property'} (string, Enum: `3.7`, `3.8`). Kafka major version.
 - [`letsencrypt_sasl_privatelink`](#spec.userConfig.letsencrypt_sasl_privatelink-property){: name='spec.userConfig.letsencrypt_sasl_privatelink-property'} (boolean). Use Letsencrypt CA for Kafka SASL via Privatelink.
 - [`private_access`](#spec.userConfig.private_access-property){: name='spec.userConfig.private_access-property'} (object). Allow access to selected service ports from private networks. See below for [nested schema](#spec.userConfig.private_access).
 - [`privatelink_access`](#spec.userConfig.privatelink_access-property){: name='spec.userConfig.privatelink_access-property'} (object). Allow access to selected service components through Privatelink. See below for [nested schema](#spec.userConfig.privatelink_access).
diff --git a/docs/docs/api-reference/postgresql.md b/docs/docs/api-reference/postgresql.md
index 7d637c19..5cff1446 100644
--- a/docs/docs/api-reference/postgresql.md
+++ b/docs/docs/api-reference/postgresql.md
@@ -211,7 +211,7 @@ PostgreSQL specific user configuration options.
 - [`pg_read_replica`](#spec.userConfig.pg_read_replica-property){: name='spec.userConfig.pg_read_replica-property'} (boolean). Should the service which is being forked be a read replica (deprecated, use read_replica service integration instead).
 - [`pg_service_to_fork_from`](#spec.userConfig.pg_service_to_fork_from-property){: name='spec.userConfig.pg_service_to_fork_from-property'} (string, Immutable, Pattern: `^[a-z][-a-z0-9]{0,63}$|^$`, MaxLength: 64). Name of the PG Service from which to fork (deprecated, use service_to_fork_from). This has effect only when a new service is being created.
 - [`pg_stat_monitor_enable`](#spec.userConfig.pg_stat_monitor_enable-property){: name='spec.userConfig.pg_stat_monitor_enable-property'} (boolean). Enable the pg_stat_monitor extension. Enabling this extension will cause the cluster to be restarted.When this extension is enabled, pg_stat_statements results for utility commands are unreliable.
-- [`pg_version`](#spec.userConfig.pg_version-property){: name='spec.userConfig.pg_version-property'} (string, Enum: `12`, `13`, `14`, `15`, `16`). PostgreSQL major version.
+- [`pg_version`](#spec.userConfig.pg_version-property){: name='spec.userConfig.pg_version-property'} (string, Enum: `13`, `14`, `15`, `16`). PostgreSQL major version.
 - [`pgaudit`](#spec.userConfig.pgaudit-property){: name='spec.userConfig.pgaudit-property'} (object). Deprecated. System-wide settings for the pgaudit extension. See below for [nested schema](#spec.userConfig.pgaudit).
 - [`pgbouncer`](#spec.userConfig.pgbouncer-property){: name='spec.userConfig.pgbouncer-property'} (object). PGBouncer connection pooling settings. See below for [nested schema](#spec.userConfig.pgbouncer).
 - [`pglookout`](#spec.userConfig.pglookout-property){: name='spec.userConfig.pglookout-property'} (object). System-wide settings for pglookout. See below for [nested schema](#spec.userConfig.pglookout).