Regular Wi-Fi slowdowns on RBK50 satellite

Hi,

I can see this issue has been widely reported over the last few years but I was wondering whether anybody finally managed to find a reason or a fix...

Specifically in my case: 

I have a RBR50/RBK 50 system with an RBR20 satellite added recently

My Internet speed is ca. 200Mbs

The system works like a charm except that every 3-4 days the Wifi speed I get on all devices connected wirelessly to the RBK50 satellite drops to 30-40 Mbs and stays there until the satellite is restarted (a simple restart fixes it, no factory reset required). 

Devices connected to the router and the other satellite always get 200Mbs, as does the computer which is wired to the satellite in question (clearly ruling out any issues with the backhaul)

Initially I used to get this issue every 2 weeks, then every week and recently (roughly since the latest firmware update - although it may be coincidental) every 3-4 days. It is very very regular. 

I did try a factory reset which didn't change anything (the speed keeps drops after 34 days)

I'm not contacting NG support about as I definitely don't want to waste a few months of my time, like many others had before, and get no solution in the end

Superusers / GURUs - please carefully read the post before replying with a bunch of random questions irrelevant to the problem (like size of the house, distance between router and satellite, Mu-Mimo, beamforming etc)

I know many ppl have been suffering from the same problem so wondering if anyone has found something useful over the last couple of years.

The only solution I can think of right now is plugging the satellite into a timer which will restart it every 4 days by switching the power off, but it's hardly ideal

Many thanks,

Peter