All videos and assets will remain in the account during the upgrade, and any new features or areas are unlocked after the purchase is complete.
Any existing credit on the account is applied to the price of the upgraded subscription.
Below is an example of how credit is applied or pro-rated when a subscription is upgraded:
Kelly paid $549 for her Premium subscription. She is 6 months into the annual subscription and has $275 of value left on her account. She upgrades to an Enterprise subscription, which normally costs $999 for an annual subscription. Kelly has to pay less today though, since she’s already halfway through the subscription, which means it would cost $500 for the remainder of time for an enterprise subscription.
Since Kelly already has $275 left on her account from her original subscription, she must pay an additional $275 today to have her Enterprise subscription continue until her existing renewal date.