Here’s the location I’m talking about.
Screenshot in OSM Standard:

Screenshot in CyclOSM:

From what I can tell, the missing section was added 6 days ago in changeset 173999775. But weirdly, some of the parts that are showing up (basically, everything west of the missing part) were also added in that same changeset, so it’s not a matter of the map not being updated with the latest data.
Does anyone have any idea what could be causing this?


Yeah that looks really close to correct. The next tile east would probably also have to be not updated, but that probably wouldn’t conflict with any of the <1week old data.
Really interesting.