I know that you can tank some seasons,
Some seasons ?
As the starting date is 2014- 2015, I would say that they stayed same lv for a year or more.
I 'm sure they did the trick with friendlies too.
If you are lucky, they will tank again.
if now with the new asso rules they will decide to promote, say goodbye to League championship for the next 5 seasons

Association cheaters destroyed the game and it will remain like this for at least half a year.