Different Time Limits in One Game

I searched, and I didn't see something about this; I wasn't sure if it was "abuse", either.  I played a game that said, in the seek, "1 0 blitz".  However, in the game my opponent got four extra seconds each turn while I got none.  Is this a bug, cheating, or is it a preset that I missed?

Time was on his side!

...Probably a bug...

it is lag compensation. he probably saw you getting 4 seconds as well :)

While we were playing, he (or appeared to, if it was lag) took up between 1-10 seconds of time each move, with an average of maybe 3 seconds; on my turns, I used 1-2 seconds.  However, my timer ran out while he still had roughly 30 seconds.  Because the range of time on his moves varied so much, I'm not sure if it was lag compansation.