After evaluating the current level of POST-as-GET support across requests to the ACME v2 API we have decided to push back our original deprecation schedule.
Previously we announced deprecating unauthenticated GET requests for the prod V2 API on November 1st, 2019. Our current plan is to use this date as the staging environment deprecation date and to remove production support one year later, on November 1st, 2020.
I have updated the original post to reflect these new dates (and to reference RFC 8555).
Thanks,