Letsencrypt cerbot-auto warns: "Your system is not supported by certbot-auto anymore"

[dsnpevl]

I've been running Let's Encrypt's certbot-auto for serveral years without issues. Recently the certbot-auto command started showing warnings:

Your system is not supported by certbot-auto anymore

I assume it is complaining about the Apache 2.4.25? Has anyone else encountered this issue and found a solution? Just upgraded to ReadyNAS OS 10.6.5 but the issue persists, since Apache is still on 2.4.25. Are upgrades to newer Apache version planned for OS > 10.6.5?

# certbot-auto renew
Your system is not supported by certbot-auto anymore.
certbot-auto and its Certbot installation will no longer receive updates.
You will not receive any bug fixes including those fixing server compatibility
or security problems.
Please visit https://certbot.eff.org/ to check for other alternatives.
Saving debug log to /var/log/letsencrypt/letsencrypt.log
...

#  /usr/sbin/apache2 -v
Server version: Apache/2.4.25 (Debian)
Server built:   2019-02-18T19:55:40

Found some pages that seem to be related to this issue, but I cannot destil a clear resolution from them and they dive very deep into the issue:

https://community.letsencrypt.org/t/your-system-is-not-supported-by-certbot-auto-anymore/139606

https://community.letsencrypt.org/t/apache-and-lets-encrypt-version-2-in-2019/93083

https://github.com/icing/mod_md/releases/tag/v2.0.3

https://icing.github.io/mod_md/acmev2.html

[dsnpevl]

Might also have something todo with the Debian 8 (jessie) version in ReadyNAS OS 6.10.5.

If I look at https://certbot.eff.org/lets-encrypt/debianbuster-apache Jessie is not listed. The debian versions in  the OS pull-down for the certbot instructions are:

Debian 9 (stretch)
Debian 10 (buster)

# cat /etc/*-release
PRETTY_NAME="ReadyNASOS 6.10.5"
NAME="Debian GNU/Linux"
VERSION_ID="8"
VERSION="8 (jessie)"
ID=debian
HOME_URL="http://www.debian.org/"
SUPPORT_URL="http://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"