Upgrade a connectport ts-16. POST upgrade needed?

Need to upgrade two older TS-16 so Edge will connect to it, and I don’t have to use Firefox with a low TLS setting to do so.
Have had no need to upgrade before.
Unit is from 2017
Part# 70002388
Currently running 2.19.1, Post is 1.13
Found the firmware on the download site, But do not see a POST update. And not sure if I need it before upgrading the firmware.
Have downloaded 82001474 already.