Ever worsening Infinity Speed from Exchange to Mod...

Question

I had BT Infinity installed in the summer, in June and did regular speed tests which were getting me approx 15 - 16 MBPS DL and 2.5 MBPS uplioad, from the exchange to the modem
5 months later, I now get 7 MBPS DL and about 1 MBPS Upload
Thh BT speed check say I could get between 20 and 26 MPS - ive never believed that, and was happy with the 15-16 I was getting, but being down at 7 is pathetic.
Nothing has changed. Anyone any idea why?

Answer 1

Ok - so an update to this:
i just received a call from BT, who told me that regarding my issue they have identified a fault in the exchange which is being worked on, and my normal service would be restored by 8 PM tomorrow. It wont require an engineer to visit my home (as expected).
When I then pushed her for info on what the fault was, she said there was some planned work going on in the exchange and it was affecting lots of other people as well. Im annoyed I didnt ask more questions abot precisely what she meant by "exchange" in the context she said it.
So clearly, she is just reading some generic notes from a helpdesk system and wouldnt be in possession of any particular info to my fault. I asked what would happen if the service wasnt restored by 8 PM, she just said it would be.
So, i wonder whether there is some deliberate work being done by BT to manage demand / capacity, and the speed was being kept lower than it could be during this planned work on purpose.
Either way im intrigued to see what happens tomorrow at 8PM. Im:
30 % expecting it to be fixed
50% expecting no change
20% expecting it to be worse
Bearing in mind they referred to planned work, I'll wait to see what happens then phone BT asking for a partial refund of the broadband part of my bill. Might get £5 i suppose!