What i got from Meraki support:
Hi,
Thank you for contacting Cisco Meraki Technical Support.
You may check the MAC forwarding table on the switch as information for AP's MAC should be kept there for few minutes.
However, the best practice would be use port 'name' configuration option on the switch to put information about AP it's connecting to or 'Notes' section on AP to specify switchport information.
Please, let me know if you need any further assistance. Otherwise, as I have answered your question, this case will be automatically closed in 3 days if I do not hear back from you by then (however, we can easily reopen the case if you require more information, please email or call the Support Hotline if you wish to continue).
Best Regards,
Cisco Meraki Technical Support