If, before the end of the initially chosen subscription, the Customer decides to purchase a subscription with more functionalities (Upgrade), (s)he will be charged the full value of the new subscription minus the value already used on the previous one, calculated on a daily basis (pro-rated), without any discounts or coupons eventually granted at the time of the initial subscription.
For technical reasons and to comply with our Terms and Conditions it is not possible to automatically downgrade active subscriptions, i.e. to move from a subscription with more features to one with less features. This would potentially make us automatically deleting some of the content already saved by you, which would be a violation of the Terms by us.
If you wish to downgrade, you should contact us via Support Centre and we will do everything to find the best solution for you. In any case, this operation will never imply the return of amounts already paid and not used.