TL;DR -- Google found bug in Windows 8.1. Gave Microsoft standard 90 days notice of public release on 11 January. Microsoft wanted to move release date to patch Tuesday on 13 January. Google released on their 90 day notice date of 11 January. Personally, I don't think Google should bend to the internal red tape of other companies. You are going to start maintaining this long list of exceptions based on other peoples…
Engineers love zero tolerance policies, but that doesn't mean they are the best choice in every situation. A little wiggle room doesn't end the world.
You start out with two days because of patch tuesday. Then next time a bug is reported, well, this is a busy month with lots of people on holiday, if we could have an extra 10 days? And the next time, we're really close to releasing Service Pack N, the fix will be in that but it's got lots of changes - it'll be out in 60 days...