Last Update vor einem Jahr
There's no specific feature for this, but you can easily do it with Bulk Upload.
Enter the image in the link column and select a different subreddit in each row. Use the best_[date] option in the post_at column to get the best time for each day.
In this example, the selected image would be posted to subreddit1 on 27th, to subreddit2 on 28th, and to subreddit3 on 29th.