No, plans cannot be changed at this time, once applied to your account.
Please be aware that you should not cancel your QC Viki Pass subscription after you become a QC or apply your code. If the plan is cancelled, you’ll effectively lose your Viki Pass benefits on the next renewal date, as there is no card associated with your account.
If a card is in fact present and you resubscribe again after that, it will effectively charge you for the subscription. In case you mistakenly cancel your subscription, please write to us directly to revert the mistake so you don't get charged for your QC benefit Viki Pass subscription.