Thank you @TP-Link !!! Picked up a TP-Link gigabit 5 port unmanaged switch today. Turned everything off while I hooked everything up and then powered things on. Was blinking red for a while and then...

@TP-Link, Thanks again for the quick responses. I'll get a stand alone switch and give that a shot. Hopefully I could find something in the next couple of days.

@TP-Link, I can confirm that with either Unit 1 or Unit 2 as master, the second unit cannot be plugged into ethernet or it will create an unstable network which will eventually block access to the...

@TP-Link, The units were initially configured in AP mode and have never been put back to router mode. I tried switching Unit 2 to master as suggested. When I did that, I left the previous master...

And, yes the link you provided is the correct hardware. It would be the version 2 unit.

@TP-Link , Thanks for the quick reply. The diagram you provided is correct. At the moment, after encountering the issue, the secondary is wireless back to the primary. It worked fine for a bit over a...