The next possible termination date is essentially the maximum of minimum term, period of notice and cancellation period. For example, the minimum term is 90 days, the period of notice is 42 days and the cancellation period is 6 weeks.
The minimum term of 90 days here has the highest value among the three periods. As such, the first possible termination date would be 90 days after the date of subscription of the displayed offer. Additionally, the period of notice agreed on being of 6 weeks, the notification of termination would be due 6 weeks before any effective termination.