Existing subscribers move automatically without a price change. Max 5x becomes Max at $100 a month and retains its five-hour cap. Ultra provides ten times Pro’s weekly capacity, according to the documentation, so it is not unlimited.
Ultra verification happens automatically using factors including account and payment history. A temporary cap applies until then. Verifying a phone number alone does not remove it. Subscribers can check verification by the absence of a session bar in usage settings. Mobile prices may differ.