Yes but it will be halved. Unfortunatly so will your agent. If you take note of the ammount of spy protection you have you can work out when you can spy attack.
Just remember every tick you lose 1 tick of spy protection and every tick your agent gains a tick of infiltration and when the infiltration because greater than the spy protection you should be able to succesfully spy attack... Unless he adds some of his own
(Just make sure you account for both the spy protection and your agent infiltration being halved. This happens every time an outpost changes controll between a player).