Yes, that icon you circled indicates it is uplinked via mesh. Is it plugged into the “GF Switch”? Can you tell what the link speed is of the interface that goes to the AP? Assuming it has link?
If its connecting via mesh and it shouldn’t your options i would recommend would be -
Re-terminate the cable
Pin test the cable
Disable mesh on that AP or all AP’s if your not using it. (recommended as can cause network loops unless you only using the Alta switches which i believe may have STP could be wrong)
I was referring to the link negotiation speed which can be seen on the switch itself (if you have link lights enabled) or in the cloud UI like so:
Orange interfaces are negotiated at 100mbps, purple at 1gbps.
If you’re seeing 200mbps real world throughput, that’s a 100mbps Full Duplex negotiation, 100 up / 100 down. And since the AP is flipping over to mesh, that’s likely a bad Ethernet cable. Clue 1 is the link speed not negotiating at the full 1gpbs Full Duplex, clue 2 is mesh should only kick in if there’s no Ethernet link, so it seems the Ethernet link is dropping from time to time or quite possibly over and over right now.
Disabling mesh in this circumstance would like result the AP simply dropping offline. As it stands now, the network is self healing.
The best route, as @LincsWiFiSolutions states, is to re-terminate that cable or replace that cable if re-terminating is not an option.