I'm saying this for ANYONE who wants to use a platform:
If they have an agreement you need to sign, for the love of god READ the damn thing no matter how long it is. If it has a clause where they can change the terms at anytime after signing a legally binding contract do not trust that company. The Unity thing wouldn't be that big (still a dirty trick) if they didn't add in that they can just change things to your contract. Because had they not added that, they wouldn't be able to charge people who already had a contract with them and if they did....well lawyers would have a fun time.