You can also find a statement from Josh Aas at
explaining all of the rate limits.
We are exploring a way to exempt renewals from the rate limit because it's not really correct behavior to prevent someone with an expiring certificate from renewing that certificate due to rate limits. This is discussed at
If your domain is shared with a large population of other users (like a free DNS provider or an ISP), it is possible to get an exemption from the rate limit by having the domain owner get itself added to the Public Suffix List, although this isn't going to be the preferred long-term solution for this situation.
Sorry for the inconvenience and I hope your renewal is successful before your certificate expires.