Could be an option (tick this box style) when you set up the game to AUTOMOVE (there's that word) when everyone has entered a bid like CC said in his lst post, just like setting time limits and number of players and ratings etc. Last person doesn't get a chance to change their bid ... part of teh penalty for being the slowest.
You could also (for a fast game) make it the last person to bid also leaves the game, more like maybe a bird gets them for being the slowest. That would speed some people up, the automove would then kick in after the second lst made their move.