Brief disconnect​s every 15 minutes

I'm getting the same issue as this thread:

http://talktalkmembers.com/t5/Superpowered-Fibre-Broadband/Brief-disconnects-every-15-minutes/m-p/1924698#M111189

My super router model is HG633. Not sure if it's related to the software version v1.18t because cannot be certain exactly when the error started. I know it's been happening for a number of weeks though.

See attachment of my system logs for today.

I have already tried a factory reset which has made no difference.

I'm running on super fibre large and getting about 65MB downstream and 20MB upstream.

I'm also getting a lot of Security Warning Intrusions but don't know if that's related?

Are there any known solutions to this issue?

Any help appreciated.

Thank you in advanced.