Security Update 2015-004 Yosemite

Has anyone else noticed that Apple already released "Security Update 2015-004" for Yosemite back in April?

When I click the link to the Apple KB article it lists "Security Update 2015-007" for Yosemite was released on October 21st 2015. Anyone else concerned about this discrepancy?

@Widner That's interesting, https://support.apple.com/en-us/HT204659

Well, it looks like 2015-007 would be the next security update for Mavericks, but 2015-004 for Yosemite? They need to be clearer about this, but it makes sense to me, their naming convention is simply terrible.

I emailed Apple Product Security and just received this response:

Hello, Thank you for your question. The Security updates we released were OS X 10.11.1, Yosemite Security Update 2015-004, and Mavericks Security Update 2015-007. We will update our Security Content Pages to reflect this. Regards, Apple Product Security