Your router stats do not appear to show a problem so once G.INP kicks in again then you should get your previous speeds back.
As said earlier this can take up to 14 days.
Why would you expect to get any more than previous? You will only ever get what your line is capable of no matter which package (or package name) you are on.
After the initial line speed test and looking at the upgrade the order spec said and estimated: We estimate your download speed will be between 25Mbps and 35Mbps so I was expecting something in the high twenties rather than the 25mbps max I previously had. Now its at 21mbps. They dont explain you may have to wait a fortnight to see any increase in speed, thus causing frustration and resentment.
TBH I think no-one realised that the line would be reset. We certainly didn't on here until other users started reporting the problem.