Not sure if the discussion is referring to AA50 (anniversary) or Global.
Here are links to PDFs of the rulebooks…hope that’s helpful.
For Pac 1940 (same rules as Euro 1940)
Amphibious assault: Can you move naval units that don’t bombard on the non combat phase?
AA Anniversary edition 1941 scenario:
America has a destroyer in sea zone 12
sea zone 13 empty
Morocco Algeria has 1 German infantry
America has Battleship, cruiser, aircraft carrier w/2planes, 2 transports in sea zone 10
sea zone 11 empty
America has 2 infantry 2 artillery in Eastern USA
I move fleet from Sea zone 10 to 12 doing an amphibious assault. Does that make sea zone 12 a combat zone? Does sea zone 12 become a combat zone if i offshore bombard?
Is it possible to move destroyer from sea zone 12 to sea zone 13 during non-combat move after the amphibious assault is over?
Can I separate the destroyer from this amphibious assault so I can move it somewhere else?
Since there was no sea battle in sea zone 12 and the destroyer did not participate in the amphibious assault, it did not participate in combat and is therefore free to move in noncombat movement.