My 4G-router drops to 2G EDGE after running couple of weeks. It's a really weird thing, since it does not do it always. Also the total on-line time is really weird. I hardly think that the on-line time can be 9 years or so.
I could not find any other remedy to fix this, but to reboot. After that it does a scan for connections and finds 4G/3G/2G and chooses the fastest one like it should do.
This is just a nuisance. I'd expect the box to be a little bit more robust.
The on-line time calculator -thing is a really weird one. It seems to jump 200 days during 8 hours when it feels like doing it. Apparently the entire calculator is busted.