I also also wondered why the SRS remained engaged during windshear and did not automatically disengage at the acceleration altitude as it is supposed to (normally, as per FCOM)
So do you agree that the answer to my question is what I posted before about the Windshear Detection Function? From what I now understand, it provides a special kind of SRS, and the FG part of the FMGC knows it is in the middle of a windshear encounter, thus modifying the SRS orders, and keeping it engaged.
I'm still not 100% sure, just the best answer I have right now.
Cheers.