[rvdginste]

We intend to do something similar. The users get a pop-up in the front end when a new version is available and are asked to load the new version, but they can keep on using the old version for a while. The length of the time window does not really matter that much: whether it is 5 minutes or several hours, the issue is the same. Regarding the database upgrades, I believe that if you really want to, you can split up a not-backwards compatible upgrade into multiple upgrades that are each one on one backwards compatible. But that is extra work and like you said you really have to think those things through for every change you roll out. So I think the extra effort is not always worth it and also I wonder how other people are approaching this.