Payment methods for Bubble subscription and additional capacity

Question regarding the Bubble subscription-plans: if you want to change your professional plan from paid yearly to paid monthly, can you cancel your current yearly Bubble subscription and then subscribe to a monthly one? Will the remainder of your balance (if you’re only one month into your yearly plan) be transferred back to your creditcard?

The reason for asking is that additional capacity units are also billed yearly on a yearly plan. I presume that on a monthly plan they’re billed monthly? When you have to pay upfront for a whole year for a unit (240 dollars that is), scaling obviously has severe financial consequences for the short term.