Okay with the office empty I have rebooted the TC440 and HG659. Speed is close to what it was yesterday that is 897mbps download and 94.6mbps upload and 9ms ping. Shouldn't need to reboot every few days, this is silly. ...
Yes, it is.
If you stick with cable you should reboot at least once a week - it does improve performance (for a while ).
Personally, if I had the option of getting "real" fibre, I would take it, regardless of price.