They didn't just cheat for years. They started cheating the very moment the salary cap was introduced in 1999 and were well known for they activities in real estate. At the time, it was considered more of a joke that they threw good money after bad on star names that they couldn't get to play as a team -- Castanets and Broken are a couple of examples from around that time. The trouble started when they started to win stuff and left other teams unable to compete...
The good news, it's all catching up with them, even though they've not been taken to task for every bit of cheating that they've employed over the years. I really hope the Championship agree on the £2.5m salary cap for next season.