When performing a major server version upgrade (e.g. to MongoDB 7.0), Atlas automatically set the Feature Compatibility Version (FCV) flag to the same version.

We would like to see this be a two-step, i.e.
1. When upgrading to 7.0, Atlas keeps the FCV pinned at "6.0"
2. 1~2 weeks after upgrading, Atlas reminds us increase the FCV to "7.0", i.e. once we've seen it running stable.

We had a major production-outage issue in upgrading to MongoDB 7.0 and because of the current Atlas FCV behavior we could not downgrade back to 6.0.

We understand that some users don't care about FCV, so for such users there could be a "YOLO" mode which is the current behavior. However, we don't think YOLO mode should be default.

It seems there are a number of similar feature requests, e.g.:
- https://feedback.mongodb.com/forums/924145-atlas/suggestions/40881025-have-the-ability-to-downgrade
- https://feedback.mongodb.com/forums/924145-atlas/suggestions/42176614-major-version-downgrade-request-4-0-to-3-6