As far as any of us know, there is no deadline for finishing Part II. (At least none that we've ever heard of.) You might drop Prometric an email and inquire just to be certain as you work on it, but you shouldn't encounter a problem, I think.
Theodore Jonathan Casser
SCJP/SCSNI/SCBCD/SCWCD/SCDJWS/SCMAD/SCEA/MCTS/MCPD... and so many more letters than you can shake a stick at!