Merge with https://github.com/nodejs/Release project?
Since they both are tracking the same JSON data separately
+1 And it will be easier to maintain. I think the issue should go back to the TSC or admin (via Release)
This is separate from https://github.com/nodejs/Release, although it does expect the data fed into it to be in the same format as https://github.com/nodejs/Release's schedule.json. I'm guessing https://github.com/nodejs/lts-schedule/blob/main/lts.json was added as some default example as a copy of the one from the release repository but as can be seen from the git history it hasn't been updated since the initial commit.
I would be -1 merging this with https://github.com/nodejs/Release as it's not specific to Node.js releases (e.g. https://github.com/nodejs/lts-schedule/pull/6 generalised it for use with other projects). I'm not even sure that the Release WG even has write/maintainance access to this repository (outside of those members who are also org admins/on the TSC).