I'm cutting into an existing CPVC water line to add an outside sillcock.

I shut the water off and drained the system as best I could. I cut into the existing pipe and, after it stopped dripping, I wiped it dry and cemented in a new CPVC Tee for my sillcock. About 2 minutes later, water (apparently still draining from in the house), started to run out of the Tee. Could this water have compromised the integrity of the new cement bond? (It wasn't under pressure, just residual water draining past the newly cemented joints.)

Any thoughts/comments would be greatly appreciated.

Do you mean that a little water ran out the open end of the tee or pipe and you are concerned about the bond? If so, not to worry.

You should be OK. The joint became water tight the minute you glues in the tee. Since the trickle wasn't under pressure it's my belief the joint will hold. Good luck, Tom