Well I've come to accept bugs as a part of the overall process. There will be bugs now, and there will be bugs later. As long as we're working towards solving them, then eventually we'll be one step closer to a better game overall.
The team I have in Expeditions all had 20XP last night. Now they have 3XP.
The key stat is the level, they are gaining exp not only from the XP Creator, but also from the expedition itself (when it completes), so depending on how much they gained, a level-up might have occurred.