I go with MuadDib's implentation of ket's solution

1 Week every month seems good to me, I could even say it seems little, but that's probably just my eagerness speaking.

Could you start a 3 player game on the 4 player table?
Not if connecting to the table remains the same. It's like trying to start a 1p game at a 2p table. The game will start once first two players "ready up". So, unless a change is made in that department, you can't. There might also be some server issue if it was designed for 4 players, but I wouldn't know anything about it, just my guess.