What’s this about 10.15 Supplemental Update 2?

In the last day or so, rumours have spread about the appearance of macOS Catalina 10.15 Supplemental Update version 2, usually accompanied by scorn at Apple having to release a second emergency update within the first few weeks of the release of Catalina 10.15 itself.

Well, looking more carefully at what we know about this, there’s a much more obvious explanation. It’s not yet another emergency update at all, but the result of Apple updating the security certificate on the original 10.15 Supplemental Update (or 10.15 Update as it seems to be called officially).

As I wrote, some of Apple’s security certificates expire on 24 October 2019. I think that you’ll find that list includes that first update to 10.15. So Apple’s primary purpose in posting a new version of that update is actually to update its security certificate.

Next, look at the build numbers. The original update was 19A602, that of the new update is only 19A603, a single increment. So yes, it is a slightly more recent build of 10.15, but hardly something you’re likely to notice. Not only that, but it’s accompanied by identical release notes, suggesting that little of significance in the update has actually changed.

Not only that, but if you have already installed the first version of the update, you won’t be offered the second – there’s no point. The only value of the new version is for those Macs which haven’t had the original update applied yet. It there ensures that, after 24 October, its certificate will be valid, and you can install it where needed.

So let’s just hold onto our hats for a second, and stop jumping to unfounded conclusions yet again, please? Catalina isn’t a complete mess, except in our own minds when we want to make it so. And if you don’t believe me, check with Mr. Macintosh, who has found exactly the same.