I usually SOIC clip/backup the firmware on Ubiquity and other devices we own, before doing anything like this (more recently). Its usually so much faster and reliable than an RMA in most cases for a simple firmware update fail, especially with the post pandemic supply chain the way its been.

Took awhile to get the approval but when you have a large pile of RMAs sitting for 6mo to a year due to a bad firmware update, for only a standard 1-2 year limited warranty, and they stop responding, and replacements were back-ordered for ages. Well, you do what you have to.

That's the trick, the dumb wifi APs don't update.