Marshmallow Update for AT&T Phone on Cricket?

[AC Question]

I have an AT&T Note 5 (N920A) running on cricket wireless and want to upgrade to marshmallow from 5.1.1. I can't get an OTA update, and apparently you can't flash firmware to the AT&T Note 5, so is there any possible way to get the update?

 

[Rukbat]

You can try the AT&T Note 5 forum at XDA Forums.