We've updated our rate limits. The updated limits are reflected at https://letsencrypt.org/docs/rate-limits/.
The changes were:
- 20 certificates per registered domain per week (up from 5).
- Added an exception to this limit for renewing certificates (issuing a new certificate with same names as a previous one).
- Added a new limit on issuing certificates with the exact same set of names: 5 certificates per FQDN set per week.
As always, we'll be evaluating these on an ongoing basis and will tweak them as needed. Note that if you have a domain with more than 20 subdomains, the exception we added for renewing certificates allows you to gradually increase the number of certificates you can issue over the course of multiple weeks.