The uploaded leads limit counts any contact that you have uploaded to Instantly and that is in the campaign (active or paused).
Growth plan has a limit of 1000 uploaded contacts and Hyper Growth plan 25 000 contacts.
The uploaded contacts limit is fixed.
These do not work like credits, and do not reset every month.
In case you want to create space for the new leads, there are a few options:
Opt for add-on
Delete campaigns that you no longer need
FAQ
Q: Can we restore leads that we deleted?
A: The deleted data cannot be recovered.