With the loss of PLAY, it wouldn't surprise me at all if Icelandair eventually announced STN. Tbh I'm surprised that Icelandair doesn't already operate to STN. With its hub at KEF and it's many connections it makes perfect sense for Icelandair to serve STN alongside LGW and LHR.
Regarding possible airline additions at STN.
Now that Airblue and PIA have both been given permission to resume flights to the UK, I wonder if we will see Airblue at STN at some point 🤔
And looking slightly further ahead, the possibility of IndiGo 👍