Upgrade of STG .com databases on weekdays

Summary

In the past, STG major version upgrades for .com Postgres databases were performed on the weekend, but now we have more databases (added Sec) and more steps for this upgrade cycle (added OS upgrade).

DBO would like to perform the remaining STG database upgrades for .com (CI, SEC and MAIN) to weekdays. just as was recently did with STG REGISTRY. Requesting permission to upgrade STG CI by no later than 2025-06-16 and 2025-06-17 during AEST business hours.

This is only for STG, PRD will always be done usually on the last weekend of the month.

This request is to avoid having teammates work too many weekends and also to have supporting team, like Dev_Ex (QA), ready to assist when needed. Otherwise, supporting teams would also have to coordinate weekend coverage for our STG upgrade activities.

If allowed, how should go about picking good dates? What standing events do we need to avoid? Thank you @gitlab-org/release/managers @gitlab-org/delivery for your consideration.