Search this topic for "149" and "DFS". It appears that U-NII-2 and U-NII-3 channels are available if your country does not require DFS for these channel ranges. For example, a user from India reports using Channel 149 at 23 dBm.
The general consensus in the topic linked above appears to be stick with flashing 22.03.2 or experiment with the current snapshot version; however, to avoid trouble, do not flash 22.03.3, 22.03.4 or, considering how little changed in it compared to 22.03.4, 22.03.5. YMMV of course - that is just my interpretation from skimming the topic - I do not own this device.