Special Custom Post Type with Limitations

Hi There!

I have a specific question about custom post type. i actually didn’t know how to search, if something similar is already discussed or somewhere else posted.

i would like to create a cpt with specific requirements:
1. the input should be a single page, where you can select the post which already is published or create a new one — based on a date.

2. in the edit-page (admin-area), if i change the post (for example with a drop-down), the other post should be saved.

3. there should be a limitation, so that only 3 posts with specific slugs could be shown – not dependig onn posts itself!
–> should look like:
https://www.example.com/cpt-slug/specific-page-1 –> shows the post with the date of today,
https://www.example.com/cpt-slug/specific-page-2 –> shows the post with the date of tomorrow,
https://www.example.com/cpt-slug/specific-page-3 –> shows the posts within a specific date range

other url’s should either redirect or show a 404.

i don’t need code or something, just ideas or maybe similar cpt’s, or tips, what would be the best way to implement this.
maybe a cpt is the wrong thing?

looking forward for any suggestions/ideas/etc.

thx in advance for every response!!

cheers,
Sahin