Downlink Max Rate per SM has been introduced starting 4.6.1-RC14 Beta firmware for TDD mode both for 802.11n and 802.11AC devices.
The feature gives the ability to limit Downlink Max Rate on SMs individually.
In Follow AP’s Configuration(Auto) mode, SM is following Downlink Max Rate configured on AP.
If any other option is selected on SM, then SM is ignoring what is configured on AP.
AP(DS MCS 7) - SM(Follow AP’s configuration(Auto)) → SM’s DL Max Rate is limited to DS MCS7
AP(DS MCS 5) - SM(DS MCS 8) → SM’s DL Max Rate is limited to DS MCS8
AP(DS MCS 7) - SM(DS MCS 5) → SM’s DL Max Rate is limited to DS MCS5