The midfielder is on loan at Nottingham Forest and targeting promotion to the Premier League but has refused to shut the door on his Toon career.
With Forest chasing a play-off place in the Sky Bet Championship, Colback said: "My situation at Newcastle looks pretty bleak, with Rafa.
"That is one of those things. I am not too fussed about that, but it was disappointing with the way it ended, with Newcastle being my home town club.
"But that is football. Obviously the aim is to get Forest promoted. Then we will see.
"If the (Newcastle) manager comes calling and wants to take me back there, we will cross that bridge when we come to it.
"But we are a long way off that just yet. We will keep calm for now."