Buffer for Mastodon?

I’m looking for a comparable app for Mastodon like Buffer & Co.

I’m not interested in the simple scheduling function that Mastodon (and some mobile apps) come with, but a calendar (say: 2 posts per day at a defined time) that you can easily fill up with unlimited posts to prevent oversharing.

My Google-fu seems to have left me - or is there really nothing like it out there? Please help…