Yep. The actual AGCAS annunciation is the pair of chevrons advancing from the sides of the HUD into the center, and the blinking cross and "FLYUP" indicates that the system has engaged.

For audio, there's a very noticeable horn during recovery, as well as a "Fly up" automatic voice announcement - that's a little hard to pick up due to overlap with a call from the formation leader, but you can catch it if you listen closely.