If you can what they wrote in this link. You will understand the phenomenon I am about to explain.
https://docs.ruckuswireless.com/unleashed/200.3/c-RogueAPs.html1. Your mobile phone has Hotspot turned on. But your mobile phone is connecting with Ruckus AP.
2. Your mobile phone (as wifi client) sent Broadcast packet as usual. Ruckus AP received that Broadcast packet and transfer that broadcast packet to its ethernet port (LAN port) as usual. This broadcast network's Source MAC is your mobile phone's wifi MAC address.
3. Other Ruckus AP has received this broadcast packet and put your mobile phone's wifi MAC address into its Dynamic MAC memory.
4. Somehow, your mobile phone got disconnected from Ruckus AP wifi connection. Your mobile phone suddenly turns itself into Hotspot AP.
5. As Hotspot AP. Your mobile phone start announcing Beacon packet over the air. Sender MAC address of this Beacon packet is your mobile phone's MAC address.
6. Ruckus AP that previously received your mobile phone's Broadcast packet on the LAN cable. Now it also received a beacon packet from the air with the same phone's MAC address. This MAC address then be identified as "Same network rogue" (see the link about Same-network rogue).
Hope this answer the one year question.