I'm guessing that they already have the model ready and the announcement blogposts locked and loaded, and then release them as soon as they see a competitor make the first move, trying to overshadow the first announcement or at least be swept up in the hype just as people start talking about new models again.

I think this one is just a coincidence, bound to happen given the pace of releases

For exact timing, probably 10-11am Pacific is just optimal for normal working hours

Maybe it‘s the Nash equilibrium from a timing perspective?

Like the reason that close to a McDonals there is usually a Burger King.

The joke is that McDonald's spends hundreds of thousands of dollars to identify new locations - traffic studies, visibility, demographics, nearby traffic generators, site characteristics, drive-thru feasibility, etc. They have one of the most rigorous processes in the industry. Burger King's process is to open a location across the street.

I think the story was Starbucks -> Seattle's Best Coffee, not McD's --> BK. but it does work I guess.

I actually heard it as Walgreen's -> CVS

makes me wonder if the starbucks story is fiction too :P

reminds me of SBC's (Seattle's Best Coffee) strategy, which was decidedly not Nash: put a store across the street from every Starbucks.

Competition. You don't want to lose your customers trying out the competitors updated and better product. Release on the same day and they won't be able to compare their new to your old.

But how do they know what day is that? Unless you have already something ready to be announced (and you just hold it until the very last moment, which doesn’t make sense, since you could just announce it asap)

It can also be ”we are done but wanna test it more and tweak it” and then ”oh they launched now. Let’s launch then as well”

All the people who are any good at AI talk to each other. There's no secrets among those who are making 7 figures plus in this field.

"keep refining and testing it until we're really done or somebody else releases"

Maybe a little corporate espionage.

Probably more keeping an eye on the behavior of the competition and predicting what they might do and adjusting your own schedules.

They get to compare their model to the old ones from the competition.

In this case, ChatGPT 5.6 Sol / Ultra releases tomorrow, so today is the last day Grok can compare Grok 4.5 to Codex 5.5. If they did it tomorrow people would point out they're comparing themselves against old models.