It might, it might not we have very few firm details to go on.
e.g. it could be the sales estimate was wrong, or poster recalls an advert rather than a sales estimate, or they were plain mis-sold the service.
service is still configured as 40/10 somewhere e.g. in the PlusNet side which can be a bit sticky.
To unravel the puzzle a screen shot of the actual sync speeds (screen shot to avoid any typo or missing important info) is needed.
If there is a worry of a mis-selling then again sync speeds from before and after and a location for the poster is needed to assess that.