The cease fire is tactical stand down to allow Hamas to reveal itself. You cannot shape the battlefield if you don't know where it is.
Withdrawal is not an option. Credit Hamas for being smart enough to see this "cease fire" for what it is, let's see if (hopefully) they'll come out and fight (and die) some more.
In any case Israel needs to reload and rest its fighters.
Oh look at this, Israel to cease fire and if Hamas ceases fire to leave at a time of their choosing. So far, so good.