I just noticed that my emacs function for creating Blot posts included a “slug” element in the front matter. Slug is not an officially supported item, and doesn’t work like one would expect. I have links configured as YYYY/slug so I would expect this post to end up at /2023/blot-permalinks, but if I put slug: blot-permalinks in the front matter, the URL ends up as just /blog-permalinks (no year).
I normally add slugs to front matter so that if I change the post title later, old links will still work. While I could add a “Link:” front matter element that includes the year, I think I’ll just leave it out and let Blot handle things.