Four times tonight I went to a Dr. Ka blast alert and as soon as the party engaged the first mob
in the street everything froze and I got a server not responding message.

Always at that point. Everything moved forward after that.

i had that happen once tonight and an awful lot of choppy lagging through much of it.

Happend again tonight and I asked the team about it.
At least one person responded that it has been happening in that instance 'all day'.