Based on what's visible of the text it's not. It seems to be something to do with the turret, possibly locking its arc. Based on that, I'd guess the full title of it is "BTL-A4 Y-wing."
Which makes the current Y-wing a BTL-S3: we've got the two man version, and the second man operates the turret.
We have the A4, it says so on the flavor text of Gold Squadron Pilot, but I'm not gonna start that argument again.....