A lot of personal sites such as this one are built on a public repo someplace, and one is often invited to submit typo corrections etc. upon finding the source. In this case, though, my search dead-ended at code for your custom, minimalist static site generator. https://github.com/evmar/cms
Date stamp is part of the metadata passed into the generator, according to https://neugierig.org/software/blog/2022/10/blog-software.ht..., but I don't see anywhere that the Go code checks whether a post's date is in the future. Did you intend to add a post-scheduling feature but haven't gotten to it?
Wow, you are thorough! I just include the date as metadata in the post input file and typed it wrong this time. I don't have any scheduling feature, the whole thing is incredibly manual ("make" followed by "rsync" to publish). I don't publish my blog's source because it includes other things like unpublished drafts.