Due to the lack of documentation, below the instructions to update poste.io
docker stop poste docker rm poste docker pull analogic/poste.io docker run --name poste -p 25:25 -p 80:80 -p 443:443 -p 110:110 -p 143:143 -p 465:465 -p 587:587 -p 993:993 -p 995:995 -v /opt/poste/data:/data -t analogic/poste.io:latest