I was seeing lots of error messages like this in my #strfry log files.

relay strfry[380]: 2023-08-11 10:38:22.717 ( 587.060s) [ReqMonitor 1 ]INFO| sending error to [16]: too many concurrent REQs

I think it was due to using a #Primal instance.

So I increased the amount of connections ( maxSubsPerConnection ) from the default of 20 to 50 , then 100, then 200.

Seems to have fixed it , or at least kicked the can further down the road.