I use RUTX09 with the old but latest RUTX_R_00.02.06.1 FW (for sure there is some significant work to fix the many issues we still have on RUTX FW... and I have unfortunately the feeling to run a Beta version)
In addition to data counter reset issue (here), I unfortunately hit a new issue with data limit management... :-(
In my case data limit was reached on SIM1 and sim switch occured as expected on SIM2. However there was a point data connection failed for some reason while running on SIM2, and despite SIM1 data limit was already reached on SIM1, sim switch to SIM1 was succesful and RUTX09 continue to run on SIM1 making SIM1 data limit to be exceeded.
Obviously, I would have expected that SIM switch back to SIM2 occured right after switch to SIM1 as SIM1 data limit was reached.
Some screen captures to illustrate, and I have also a troubleshoot file available for investigation purpose.
As you can see in first capture the reported data amount is incorrectly reported to be 20.2GB on SIM1, while in mobile data (in 2nd picture) we can see SIM1 data counter is at 115.76GB and data limit was at 95.2GB... In last picture we can see the event that lead to get switch to SIM1 with no return to SIM2 as expected for SIM1 data limit reached.