How would one resolve this situation here.

Dr. Strange, who is the only person I know of that has support and flight, is in soaring mode. Let's say Annihilus is on his 6th click and has flown back base to base with Dr. Strange for some magical healing. Let's also say that Strange decides to clear before attempting to heal, giving the opponent a round to do something about it. The opponent decides to base someone with Annihilus or Strange, since is wouldn't matter.

Can Strange heal Annihilus or is the fact that both are in Soaring mode negate that obstacle? Which would make the only way to stop it be to get a ranger and blast one of them to KO.

Edit - my gut instinct says that Strange can heal Annihilus but I don't know for sure

Best guess: to inferere with healing, he needs to be adjacent; since Strange and Annihilus are soaring, the opponent will need to move a soaring character next to them; a grounded/hovering figure would not be adjacent.

Spock is correct.