Cold Lake, AB
Be careful with UBNT and IP Alias. A default route will be created for the Alias subnet. The creation of this new default route may be delayed until another event triggers it. If the sort order for this new default route appears before your original default route, and is not valid, you can lose connectivity.
In my case, I used IP Alias on the CPE's with Rocket M900 AP's. If a CPE was installed, or an existing CPE was rebooted, the new default route would appear in the AP a few (or even 24 or so) hours later.
I still use Auto IP Alias, but all IP Alias entries have been removed from every device. Turning it off, or disabling, does not work. All entries have to be blanked.