@V1MCS "us guys" don't have an issue thanks but you are not talking to Sky by posting in the forum.
Slow down at busy times can be caused by contention, ie other customers competing for limited bandwidth ,which with full fibre is possible as up to 32 lines share a 2.48Gb/s link to the exchange. In practice though that is extremly rareas almost everyone only uses a small % of the bandwidth they buy. That limitation is down to Openreach's GPON system so isn't under Sky's control. Sky regularly measure the download speed which you can access via the Service Checker if you click on the broadband link. An even rarer issue is contention on Sky's backhaul from the fibre exchange but I think you can discount that.
Most likely that if you are using WiFi it is interference from your neighbours' networks. This issue is obviously worse in blocks of flats or dense neighbourhoods. Improving your wifi set up can help.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
