No necessarily, given the amount of islands on the map it would be very easy to have enemy ships spawn behind them, realistically there areas to place more spawns than can be covered by the few ships in the mission
Literally anywhere but right next to a player, the more ridiculous thing about that encounter was that I was trailing the stern of the convoy by at least 15km when the cruisers spawned next to me, you could have drawn a 15km radius around the convoy and picked literally any other spot along that line, but instead it opted for right on top of a player.