I reenlisted in april with the option to reclass..I have set date for AIT in August 2008..My question is can my unit stop me from going to ait if they come up on orders to deploy?

Stop no, delay yes.

If your unit is stop-moved, you will be deploying with your unit (unless you are exempt by your command or extended under the BEAR Program).

If you deploy with your unit, you will be given a new class date no earlier than 90 days after redeployment.