Assalamu Alaikum, hey there!
I've just searched the news about Zorin OS 18, and according to the official website, the OS is planned to launch this year, based on Ubuntu 24.04 LTS considering it's currently the latest LTS release. However, I think skipping 24.04 and waiting to launch Zorin OS 18 with 26.04 is a great idea!
- If Zorin OS 18 were to release with 26.04 LTS, it'd be supported for 2 years longer than if it were released based on 24.04 LTS.
- The latest LTS build often comes with bugs/fixes from the preceding LTS build; however, whilst the LTS build focuses on stability, Zorin OS likely fuses it with awesome modifications and customisations!
Keep in mind though, The new LTS build is expected to have a few bugs upon release. Hence, Zorin will have to wait for a few months until 26.04 is stable enough to be based off of.