Slow speed. Downgrade?

[#1]

Hi, so I was getting speeds of 50+mbps from roughly a year ago up till last week. Now hitting 20mbps max.
Worse, it looks like my package (£19.99 fibre unlimited) has been downgraded to 40mbps max at £14.99. Guess I never got the memo. The new replacement package? You guest it, £19.99 for up to 76mbps.
This is daylight robbery. You can't downgrade me and continue to charge the same as the newer, better replacement.
When I go to upgrade through my account it won't let me either.
Any help appreciated!

[#2]

That is all I get when trying to choose a new product.
All I want is a Fibre Unlimited Extra, which is what I'm effectively paying for.

[#3]

Same boat here, as are a few others, would be good to hear from plusnet asap why we are paying 19.99 for an inferior service and how we move the better service (and continue paying the same!)