Flamingo nxt Ignoring Pass Limits

Does anyone have any instances where they set a Pass Limitation number in Flamingo NXT (say 400 passes) and for some reason Rhino/Flamingo ignored it?

Last night, I set a model to render to 400 passes, left for the night, came back and it had blown past 400, went up to 2615 passes and then stopped. Thought it was strange… Any suggestions are appreciated.