Heroku Schema load: Permission denied for database "postgres" User

ruby-on-rails postgresql heroku heroku-postgres

It appears that this is an issue in Rails itself - there is a discussion regarding it at https://github.com/rails/rails/issues/17945 - it seems that there's a commit (https://github.com/rails/rails/blob/master/activerecord/lib/active_record/tasks/postgresql_database_tasks.rb#L77) that is connecting to the posgres database which isn't permitted on Heroku so fails.

In short, for the moment use db:migrate until the issue is resolved.