Sky Fibre upload speed

Hi everyone

Around a month ago I had to unplug my Sky Q router to do some decorating. Up until this point my upload speed had always been around 6.5mb. When I plugged my router back in my upload had dropped to 1.5mb. I contacted Sky who arranged for Open Reach to come out and investigate. He spent a few hours here and got my upload speed up to about 3.5mb. Sky say this acceptable and there's nothing more they can really do. I'm on the 40/10 package.

Would anyone know why my upload took a dive after unplugging my router? I've plugged in to the test socket and still get the same results. Is it likely I'll get my upload speed back to what it was?

Thanks everyone

Broadband Link Downstream Upstream
Connection Speed 39999 kbps 3392 kbps
Line Attenuation 25.9 dB 0.0 dB
Noise Margin 5.8 dB 5.5 dB

It may be there is noise only affecting the U1, U2 or U2 upload bands, therefore very little upload signal space available.

Some routers show the attenuation from the various bands to make it more obvious.

Its possible you've got a dirty socket, but would have expected that to impact download too.