Hello,
Since #2309 there is an issue with Phinx if the migration_table is not in the default public schema.
Currently we specify the schema in the configuration, but as the class variable in the PostgresAdapter is assigned after the parent::setOptions($options), and as the verification if the table exists is done in this function as well, when it resolves the schema name it uses the default one, instead of taking the one from the configuration.