@Sunshine PS: Just in case, attached is screenshot of the System Log, which still shows a constant on-and-off LTE PLUS connection:

@Sunshine Hi, I am still in Germany, roaming with my FL1 SIM (MR600 is at the same location as before), and I did another SpeedTest. Results are still relatively good (105/41 Mbps (see below))....

@Sunshine Hi, I am now in Germany and took the MR600 with me. But the problem remains, 4G+ is on and off. I tried, inter alia, the following: Band Selection / CA set to Auto Reboot Advanced section...

@Sunshine Many thanks, I checked (with my main SIM card, same contract) as per https://www.tp-link.com/de/support/faq/3488/, and I can only see Band 3. Is there any other specific value I shd check?...

@Sunshine Additional thought (of a layman only!): Is my understanding correct that the LTE modem is a separate PCI Card (attached to the Router)? And if so, is it possible to update the firmware of...

@kernash Thanks for pointing this out, Kernash! @ sunshine Based on the discussion referred to by Kernash, I have switched to Automatic Band selection. However, even though initially Advanced Status...