@Anonymous not sure exactly what the 2 boxes upstairs you refer to are but if they are older Sky boisters and Sky have provided you with a new white Sky Max hub they are not going to extend your wifi. The same applies to Q tv boxes. Sky do sell a package that can give upmto 3 extrnders matched to the hub see https://www.sky.com/help/articles/sky-wifi-max or you can buy your own third party wifi solution if you prefer and turn off the hub's wifi which is my own solution.
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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
