As Rento said, the rules are in place : https://www.warzone.com/wiki/Seasonal_Ladder
A player may only play on the Seasonal Ladder with one account per season. Violations will be punished with a suspension on all implicated accounts.
Manipulation of the force-finish in the Seasonal Ladder is not allowed, and the use of vacations towards the end of a season leading to force-finish will be considered especially suspicious. Violations will be punished with a suspension. In egregious cases results may be modified, possibly resulting in the loss of games and/or trophies.
(Also, correct me if I am wrong, but the ladder was increased to 75 and not 60 (like the wiki says) right?