Only he knows his true motivation but it probably is to get a foot back in the door. Four months is kind of early. I don't know how much he drank but my brain was at its foggiest at four months and I was only a 15 beer a day lightweight.
One thought as far as a formal apology or amends. I was told to get some clean time prior to doing either. Time to both work on myself and for the receiver to see that I was serious about sobriety and not just manipulating again.
I'm an alkie and I approve this message.