I assume most people have a cron job to do that. The thing is, if it fails for a number of consecutive times then you won't be able to renew it for a period of time IIRC.
They have a rate limit for the amount of renewed certs. This doesn't apply if you don't reach their servers or don't get a cert.
But if you have a problem with a CA just switch to another which supports your bot (e.g. acme compliant CAs).
The private key only you have, so that's the thing you most need to avoid throwing away over and over due to a bug. If you lose the certificate, that's a public document, you can just get another copy manually if necessary.