A: Thank you, Anakin, for your question!

It’s monthly. AI Processing is included in your tier, and the allowance renews every 30 days.

It’s counted by number of stories, not by credits. Each story the AI processes (for example, one summarized or translated article) counts as one. The allowance per 30 days is:

Tier 1: 100 stories
Tier 2: 500 stories
Tier 3: 1,000 stories
Tier 4: 3,000 stories

Details: https://follow.it/readers/features-and-pricing

Does that answer your question? If you have any others, please ask!