I have a dedicated server in Hetzner and I don't understand what this means. How do they decide when the server is "used"? Based on CPU allocation? SSH sessions? HTTP traffic? Power? It's easy to shut down virtual servers and continue from the same position. It's not that easy to do the same for servers. The linked page is very unclear about this.
Previously you could only rent physical servers for an entire month. If you’re doing this the price is still the same. But going forward it will be possible to rent for a portion of the month only (x amount of hours).