@pedrot99 I have had to reject your log image to protect your privacy as it was displaying your WAN IP. If you want to post it again with the WAN IP obscured, or it might be easier to copy and paste the log as the forum software should then automatically censor IP and MAC addresses when you preview the message or post it.
I'm not seeing anything obviously wrong with the power levels you have posted to explain the reboots.
Disclaimer - I don't work for Virgin Media. I'm just another VM user trying to help out. My setup: V6 TV box, Vivid 200 Optical fibre with Hub 3 in modem mode connected to a Netgear R7000 router. Telewest/VM user since 2001.
As a Very Insightful Person, I'm here to share my knowledge. I don't work for Virgin Media.