Oh, apparently it had to be revised and will take more time to be available. https://www.certkit.io/blog/whats-taking-dns-persist-01-so-long

I am running the nachtalb fork (currently commit 082605c from this morning), which is actively implementing countermeasures, including HTML scraping. Right now, I can open posts. I don’t have to provide an account.

No, there is no fix released for this PHP vulnerability

In my current setup, I think my reverse proxy does not detect certificate updates (done by a different service), and I am just lucky that usually the service restarts because of some update before the old one expires.

Once that is solved, I am tempted to try the six-day expiration.

Did you consider the DNS-PERSIST-01 ACME challenge? You have to add a persistent TXT entry to your DNS, and then you are independent from provider support for renewals.