IIRC the pitch & roll limit for offshore operations were 5 degrees pitch & roll with 10 metres heave. The problem with being at the pitch/roll and heave limits was a 60 knot airstream getting under the disc at the top of the pitch/heave. You could only put on so much cyclic to counteract it tendency to get airborne.
To guard against this the procedure was to unload five of the rig pax and take on five homeward bound and so on. This kept the aircraft heavy and reasonably stable. In these conditions you would not plan to refuel offshore.
When we evacuated the Hermod it was fully afloat with a 55 knot wind and 35 metre heave. One had descend vertically between the crane Jibs to get on to the helipad. No problem for an empty Puma when the deck started rising but the poor old S61s were having heavy landings with full power on because they couldn't climb fast enough.