@Philipp_1975PB Hi Philipp, has your problem been solved? Seems similar to what I am experiencing with an MR600 v3 (see https://community.tp-link.com/en/home/forum/topic/603932). And I also have not...

@Sunshine (and TP-Link MR600 team generally) So, still roaming in Germany (same location). Created a new profile, ISP selection is set to automatic (note: roaming), manual band selection set to 1, 3,...

@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?...