My MR600 lasts 6 to 12 hours before slowing down, then failing to connect to 4G.

In the slowdown, it can take 5 minutes to login to the router homepage. Sometimes you cannot connect to the router at all.

When the internet drops, the message on the router is "please reconfigure your parameters" etc. A power recycle fixes everything.

I already have a mains timer turning the mr600 off for 1 minute overnight, but it can't make it for more that a few hours.

Setup is conventional, UK Vodafone, good signal (-77), just switch on and go.