Clear your all doubts with going through the FAQs
No, 100 credits do not necessarily mean 100 screenshots. The number of credits deducted per screenshot depends on the parameters specified in your API request, as different settings consume varying amounts of resources. As per now:
If you have a regular pricing plan, you can roll over your monthly credits. However, if you have a lifetime deal from partner programs, credits cannot be rolled over and will reset every billing cycle.
In the event that your subscription expires, it's important to be aware that you could potentially lose any media storage and credits that are associated with your account. It's therefore advisable to take precautionary measures by backing up your media assets and making use of your credits prior to ending your subscription.