The easter 2011 mission "Kill The Rabbit" by Agent "Elmer" in Handel's Cove has a time limit.

I opened the mission earlier the day, did kill the "Easer Bunny", did go afk on ap again.
Now the mission is gone (in my missions list) but I can re-open it in Handel's Cove again.
Ofc I still do have the lockout. I need to start over with all that tomorrow again.
I should remind anyone that you can't enter the correct DG gal if the mission is not opened.

It should be mentioned in the mission text or at least in its summary that there is a time limit on it.

I think it said Time limit 1 hour in event chat when you started mission.

Event chat is all fine and dandy, but a good summary is where such thing should also be.