Do you own the domain dc-01.com, or just a specific subdomain that’s been given to you by a vendor or something like that?
If it’s the latter, it’s possible that someone else has recently obtained more certificates for that domain Sites like crt.sh use Certificate Transparency log servers as their source, and Certificate Transparency is not a real-time mechanism; new certificates might not show up for a while (typically not much more than an hour, but it could be up to a day for most log servers).
There’s a form you can use to request an adjustment for the rate limits of your domain. I think you would need to use the same account key for all certificates with this solution. The approval process is manual and might take a few weeks.
Since you mentioned this is for developers, depending on your use-case you could also look into using the staging server, which issues non-publicly-trusted certificates. The rate limits on that server are a bit more relaxed (I’m not sure if the specific rate limits are documented anywhere, though). The directory URL for the staging server is https://acme-staging.api.letsencrypt.org/directory. If you’re using certbot, you can switch to staging by adding --staging to the command.