Yes. Wello Solutions is a pay-as-you-go service and you can upgrade, downgrade any time. Just go to the Subscription page to do so.

With upgrading or downgrading we mean that you can change plans, recurrence and number of users at any moment.

Basically, upgrading will be done pro-rata. You upgrade immediately and just pay the difference between what you have already paid for the current unused period and the new period. Downgrading will apply at the end of your current subscription period.