T Mobile Home Internet gone after 9pm

Not exactly rural. S Texas along the Mex border is a high growth area but we only had service via wireless tower at 3/1 mbit until 2022. T Mobile home internet was a godsend. We have used them for 2 years, and they are 10x to 100x better than the slow wireless tower "when they work". Verizon Home Internet also had similar good service available here.

For the last several months, T-Mobile will go dark each day at about 9pm. Both TMHI and VZ have shut this area down to new subscribers, so I cannot simply switch to VZ. I have installed Internet Connection Monitor to my browser, and we see hundreds of disconnects each day from about 9pm and continuing through the night. I am using the original Grey Trash Can Nokia. During the morning hours I will get good service with 200/20 mbit and 20-80 ms pings, however the pings even during the daytime will sometimes go over 1000ms. Especially if I begin a large download.

After 9pm, Internet connection monitor shows short periods without service, then online for several seconds, but from a practical point, the service is unusable. Pings will regularly go over 1000ms and service will drop repeatedly.

I suppose I could complain to TMHI and maybe get a new device. Since my daytime service is stellar with b66 primary band and n41 secondary, I am not sure this will solve my problem. Access to the T-Mobile network during the evening with a cell phone doesn't seem to be afffected. I suppose this might just be load shedding. Starlink is available and might be a good alternative. Any other ideas?