Time when material vs position?

Probably a dumb question but I've never run into this situation before.  My opponent has a Q, two rooks one bishop & 4 pawns  & I have the same pieces less the bishop.  I have the opponent in check and it's the opponents move.  Regardless of their move my next move will result in my winning by checkmate.  The opponent has a little over 23 minutes time left.  I have 8 minutes.  My opponent doesn't move,  resign or disconnect/abort.  I'm thinking I can't leave the game as the opponent may be waiting to make their last move as time runs out..  I sit there for 23+minutes the opponent never moves and I get the win.

Could I have lost because of less material if the opponent had made their move as time ran out and I couldn't get my move in for checkmate even though I still have time? 

No.  Your opponent would still have lost on time.  Less material has nothing to do with it. There is a rule about insufficient material to mate, but then it's a draw.

Thanks for the info.

Therefore, you do not need to play a very large amount of control online, 15 + 15 is the maximum that you can play online, in other cases you just have to wait for the end of the game in a winning position.

Thanks for the info.