UPDATE: This is now complete. We had Zero transaction loss. We had registrations completing during the process successfully. We think that 3 users had to wait up to a minute for their registration to complete (the running guy at the end of registration).
We are doing a major database infrastructure upgrade on Monday morning, Feb. 29. Most operations will not be affected, but there may be some error messages for some operations for about a minute. Users will simply be able to refresh their browsers to complete what they are doing after that 60 seconds.
We will do a fuller update one what we are doing and how we were able to do it with such minimal impact on Monday (the short version is this is very cool).