S76 on moving deck in rough seas
I'm sure you wont need reminding that the rotor disk of the S76 can cause problems during passenger handling on a stable surface. Not sure I would want to handle passengers with a S76 on a deck moving 10 degrees!!
rotorque
Can you confirm that the 10 degrees was total movement. ie 5 degrees either side of vertical. 10 degrees either side sound pretty worrying!!
As for the AP. It should normally be OFF on any moving deck as soon as you land until just before lift otherwise the AP will be fighting the deck motion and causing big problems to anybody wandering around beneath the rotor disk....
Besides the pitch, roll and heave of the deck, you should also consider the maximum wind across the deck for safe handling of passengers. From 45 knots upwards on a smooth wet deck people can soon start sliding around.