How to have more than 32 clients on QCA9888?

I have a TP-Link EAP225 Outdoor v3 which uses a QCA9888 chip and ath10k-ct driver. I haven't been able to set up for more than 32 clients. Putting one of the config files from the Candela page into /lib/firmware/ath10k doesn't seem to change anything. Can someone summarize what needs to be done?

Note that ath10k wave 1 chips such as that in the Ubiquiti AC Mesh Outdoor allow 128 clients with a default configuration. The problem is specific to wave 2.

tl;dr: try ath10k or play with fwcfg-pci-*.txt.