Friends/instance crashing when I leave

This has happened about 4 times now, maybe more with just one person, but the entire group I'm with will get kicked to login screen and the instances apparently crash (when I went into the Abyssal Depths, I couldn't leave back to the map after I finished)

Can't purposefully get it to happen, but we noticed it the most doing dailies when I'd put a portal down and leave shortly after, and thought that was the cause- but I went into a zone and left quickly but still a few seconds delay with the waypoint, and that caused it to happen, with the instance disappearing.

Anyone else having this issue?

It seems to have been happening since 3.4.3e, a week or so ago, though as noted it may have been happening longer than that, but didn't really notice it until we started grouping up with multiple people that all drop, and noticing that the instances themselves are crashing.