So... I wanted to have another go at England with my super weak team this morning and while I was making substitutions I noticed a strange thing.
Two of my new players that Nordeus added to my team after they took away all of my superstars had 12% quality. But this morning their 1,5 stars showed as 4,5 stars. I checked them in detail after the game and their quality went up to 73% and one even received a special ability.
I've already had my morning coffee so I'm not daydreaming