What sort of fibre , FTTP, or FTTC/Gfast ?, if FTTC / Gfast, is there any electrical device switching off or on at this time ,( central heating /hot water timer, lighting, that sort of thing ) and if you have close neighbours it doesn’t necessarily have to be in your home , you could have a REIN/SHINE issue.
Does your broadband lose sync ( purple light off, then comes back on ) or is it the wireless dropping , assuming whatever you are doing is wireless ( WiFi ) and not wired
