You missed one: hire one of the many existing providers of Postgres support services. Postgres have a big list of these providers. [0]
I can't comment on how well they perform in practice compared to the conventional monopolised support model that closed-source software tends to offer - perhaps better, perhaps worse - but at least in principle, the solution is there.
I can't comment on how well they perform in practice compared to the conventional monopolised support model that closed-source software tends to offer - perhaps better, perhaps worse - but at least in principle, the solution is there.
[0] https://www.postgresql.org/support/professional_support/