SonarQube upgrade Process (upgrade RDS Postgresql)

What version are you upgrading from? 9.9 LTS Developer Version System information (Operating system, Java version, Database provider/version) AWS ec2 instance, java 11, Postgresql 10.23 What’s the issue you’re facing? I have some question if you can suggest some possible solutions We have PostgreSQL DB for sonarqube which we tried upgrading. Upgrading from 10.23 to 11.20 was smooth and we see the the DB is available but as the DB is connected to sonarqube we see high CPU utilization and high number of connections after which we 502/504 for sonarQube and the instance we used are the t3.micro and t3.small . I have reboot the DB and restarted the sonar process and UI comes up but again the DB CPU reaches the 100% and max_connections threshold is reached and get 504 error and also see this error org.postgresql.util.PSQLException: FATAL: remaining connection slots are reserved for non-replication superuser connections

Any suggestion to resolve this issue?

2. We had to use the backup to revert back older version of DB but we see that there is a AWS scheduled maintenance required under maintenance & backup which happens next this week sept 17, 2023. We have this issue last week and DB got upgraded and sonarservice is down. Is there a way to skip the AWS scheduled maintenance?