I understand that there are a lot of systems that will be impacted but I don't think we should limit progress based on dependencies. It's the same excuse that's

I understand that there are a lot of systems that will be impacted but I don't think we should limit progress based on dependencies. It's the same excuse that's used whenever we try to ween off of fossil fuels. I've worked on tzdata changes in the past and whether it's announced a month or a year in advance, progress is slow until the very last minute when teams can't put it off any longer. In other words, programmers are serial procrastinators and if you give them 2 years to prepare, they'll spend 1.9 doing nothing and scramble to fix everything in a month. This might be the first big timestamp change in the US, but there have been a lot of changes like this in the rest of the world so any globally operating company has probably had to do this at least once already and should be well equipped to make this change on a faster timeline.