Sudden arrival of Shenshock and Allies Mid Battle...

on my latest foray into the Temple I was fighting Barkinar mid battle when Shenshock and his two Bugbear guards seemingly teleported into the fight. Shenshock showed up in the lounge while his 2 buddies decided to stroll in on the west door from the troll room.

I'm guessing the timer just happened to trigger during the fight but it was strange. Realistic to have them show up as reinforcements though.

So my question to any who wish to reply, has this ever happened to you?

 

I haven't seen that, but something similar happened in Welkwood bog.
There I was, minding my own business, looting some kobold corpses that were totally there when I arrived when Matel and his buddies wandered out of the right hand room on their way to the left hand room.
He wasn't a very gracious host ........

 

The other day I had just defeated the 2 lower kobolds. Had to step away and when I came back Mathel had popped in to chase us away all by himself. He sure not a friendly host.