Are you expecting or experiencing any downtimes on ocsp.int-x[1-4].letsencrypt.org? We have a few issues in our logs:
connect() to [2600:1402:a::b81a:8e33]:80 failed (101: Network is unreachable) while requesting certificate status, responder: ocsp.int-x3.letsencrypt.org
Our system currently shows a small increase in OCSP request latency but does not indicate an outage. We will update you and our status page if we find evidence to the contrary.