TDD on e4k is ready for production and improvements keep being made to it. I’d highly recommend upgrading to 5.9.2-Beta5 (in cnMaestro cloud), especially if you’re using 6GHz which requires GPS.
There hasn’t been any work put into WLR mode in a long time. The only real benefit compared to TDD mode might be lower latency/jitter on AP’s with a small number of SM’s.
Everything else about TDD mode is better then WLR… with TDD you get flexible or fixed duty cycle, GPS sync/frequency reuse, way better scaling with the platform easily handling 50+ SM’s on a AP, way more consistent throughput under load.
I really don’t know any operators using e4k WLR mode anymore.