AP = Access Point, STA = Station (client - connected to a remote AP)
I posed same question first to Cypress and they assume use of the WiCED SDK API where max_assoc is defined. They responded:
Is there a configuration file, header file or command query that shows the max_assoc value for Pi 3B?...the wwd_wifi_get_max_associations() API will check. As your STA interface is associated with an AP, softAP interface can support (max_assoc - 1) associated clients. You can use the get_associated_sta_list() in test.console example to check the same for your device.
I looked at iw list output, but that did not show the max_assoc value, to my understanding.
Thanks for reading....