Different destinations for same aircraft

I have a bunch of the same aircraft (B738) but when I get to select a destination, some have different destinations they can fly to than others. Why is this?

Maybe you don’t have enough destinations for all your planes to go. For Example- At IAD, There are 10 arrivals from SAN to IAD and 15 Departures from IAD to SAN. That means if you have 15 planes but 10 arrival slots then you can only send 10 planes to SAN but there are M-tier destinations that you can send only 1 plane. For Example- There are no normal planes coming from PRG to IAD but it is enough for a M-tier plane to go. As because there are no planes coming=no silver keys to open slots so you only have 1 slot for it to go.

Thx for the reply, but if you don’t have enough slots at a particular destination, then it just gray’s out the destination. In mine, they are available for one 738 and yet don’t even show for the next 738.

Then its a bug I think.

Place a screenshot