UK cannot land there because they did not own it at the beginning of their turn. US comes after them in the order.
You found the relevant rule and quoted it.
yes but then you’ll get a chance to shoot down his bombers with something that rolls def at at least 2. unless you have some bomber on bomber action going on…
Axis_roll is correct. Sea units may not enter or leave sea zone 16 under this optional rule. Bulgaria/Romania being cut off from the Mediterranean is just a by-product of the way the map is drawn.