Please edit /var/discourse/launcher and replace the base image version (image="discourse/base:2.0.20190906-0522") in line 91 with image="discourse/base:2.0.20190625-0946"
Rebuild the container afterwards and run the commands you ran in E-mail sending not working after upgrade. TLS 1.3 won’t work, but is the output of the other commands similar? If not, what’s different?
Could you PM me the hostname of the SMTP in case it is publicly available?