Let's say that I want to look at EvergreenFir's interactions with two different users, Noomah and Zzyzx11. First I enter EvergreenFir and Noomah as the users and enter en.wikipedia as the wiki. It shows me that these two users have never interacted. Next I dismiss Noomah and add Zzyzx11 in the user field. It shows me that these two users also had no interactions, except that's not actually true. EvergreenFir and Zzyzx11 have had lots of interactions, but because the first query automatically set my query start date to 2018-03-14, it isn't finding them. If I was paying attention and noticed this, I can manually fix the start date, but since I didn't interact with the start date field at all, it's unlikely that I would notice there's anything wrong and would just assume that EvergreenFir had never interacted with either user.

One possible solution would be to reset the start date every time a user is added or removed, but this would interfere with the use case of someone wanting to examine interactions with multiple people within a particular span of time.

My suggested solution would be to not automatically set the start date in the UI.