As stated , without the router connection statistics, recording 4.5Mb download in itself is of no use , is that inside or outside of the line potential, does it prove anything ?
You have a misguided opinion on what BT is obliged to provide to you , there is a 10Mb USO (universal service obligation) but that can be satisfied by mobile , if you have a USO ‘claim’ once accepted by BT that you qualify, it’s a 12-24 month window to get you to 10Mb on a different network to the current one , if the current one is already capable of 10Mb plus , then it should be made to provide it , this is Openreach responsibility not BT and the USO.
In your case you have already had a tacit acceptance from BT that the service currently is below the expected service level , the offer for you to leave without any contractual obligations on your part is the penalty BT pay for that , if you chose to not take that ‘release’ that’s up-to you .
If , for example, you posted your line statistics which showed a max attainable of 18Mb , then 4Mb would almost certainly indicate an issue that Openreach need to address , if you don’t think BT are ‘pushing’ OR to address this sufficiently , then change provider to one you think will push OR , but 4Mb download in isolation means nothing , for some 4Mb is all their location can expect, without your router stats we don’t know what you can reasonably expect .
If you don’t want to provide this info (and that’s fine BTW ) it just makes it difficult to know what you expect to achieve posting here , this is a customer to customer forum , not a alternative way to report issues to BT .
