I'm dealing with this right now, actually:
Namecheap supplies a bunch of wildcard SSL certs I have. The certs generally have between two and four years remaining.
My normal name registrar doesn't support API access for updates and it doesn't support wildcard SSL at all, so I can't just set up my own Let's Encrypt certs there.
Namecheap wants me to move my domains over to their service so they can handle the short expiration terms for SSL certificate re-issues.
Their service doesn't have any kind of bulk import tool for A records from the existing nameservers and they won't let me pre-stage A records until I transfer in domains. Their support DOES say they have API access, so in theory I could make my own update tool, but they're saying that it's not intended to handle hundreds of A records for single domains, but rather small updates to single domains.
I did a count: I have 1122 A records currently covered by five wildcard certificates. They want me to enter them one at a time on a web form.
I haven't decided what I'm going to do but I have about three weeks to figure it out right now.