Release notes for prior versions can be found online. At the time of Postgres Pro Standard 16 release, these prior versions were supported:
Postgres Pro Standard 15:
https://postgrespro.com/docs/postgrespro/15/release.htmlPostgres Pro Standard 14:
https://postgrespro.com/docs/postgrespro/14/release.htmlPostgres Pro Standard 13:
https://postgrespro.com/docs/postgrespro/13/release.htmlPostgres Pro Standard 12:
https://postgrespro.com/docs/postgrespro/12/release.htmlPostgres Pro Standard 11:
https://postgrespro.com/docs/postgrespro/11/release.html