Usage-based will be fine, but if you sell usage-based with a discount that assumes the customer will stay with you for, say, 3 years - this law means they can l

Usage-based will be fine, but if you sell usage-based with a discount that assumes the customer will stay with you for, say, 3 years - this law means they can leave after 1 and not stay for the full length. Then, you've given a discount that wasn't in your interest to provide.