Landline number change

My apologies for always turning up here to pick brains so here I go again..
Change initiated and will occur on 16th August from BT Fibre broadband and Phone to Sky fibre and Anytime Extra phone.

I have been informed that I will have a different phone number at that point.

Now given I have had speed issues on my existing number (well documented here on TB) can anyone tell me if changing a phone number is a physical thing in that part of my connection to the cabinet will be different OR just a virtual thing whereby the hardware [path from cabinet to house] is identical but just given a different number?

The reason for asking is that if there is NO physical difference in any part of the line wiring,I might as well try to keep the same number I have now, however if there is the slightest bit of physical change I could take a chance on that bit being what caused my throughput to be maxed at 50Mbps where all my adjacent neighbours get about 65+ Mbps. I will not initially be trying to get 80/20 performance given I could never get anywhere near my neighbours (when on both Entanet and BT 80/20) but would like to know if in future the hassle of changing numbers might solve my problem.

As ever I hope this makes sense to someone.
Thanks
Jamie

If the new provider won't port a BT number, it just means they are too lazy to do so. It won't make any difference to the line's physics.

Ah thanks for that, I�d better try to keep the existing number.