No, that is not going to happen. That would be immense storage costs, losing revenue on hw and sw all the way. And they did survive last XMas so they will have to survive this Xmas whatever happens until December, as far as ramping up manufacturing is concerned.

An additional factor is the transfer to the 6nm refresh which they likely want to do as early a possible. You don't want to have warehouses full of "old" consoles when the better version comes out...

Well, sooner or later they must start stockpiling for Xmas: in the weeks from BF to Xmas sales can easily range from 3x to over 5x (during record BF' and Xmas' even more) the sales of slower periods.
If they manage the warehouses with a FIFO order, they don't risk having them full of old stuff at the wrong moment.
When stockpiling starts depends on Xmas period sales predictions, current production capacity and how much they plan to ramp it up in the next months.
6nm is utterly desirable, I agree, but the sources I found predict it for next year, so this could be an additional reason to not ramp old tech production up more than strictly necessary to reach planned sales.
OTOH there isn't just Sony in the matter, surely AMD had a say in the deal on the minimum number of units it will produce with each major process and mid-life refresh to make them economically viable, surely in the deal there is a compromise to make both parts reasonably happy (and surely both Sony and MS are happy AMD isn't strong enough to force horribly one-sided deals like Intel and NVidia did with MS for the first XB).
Anyhow, doing a quick maths, and taking for granted that some ramping up, even little, is most  likely to happen, I agree that most probably early June is quite too early to start stockpiling... We'll have to watch sales in the next weeks and wait for more infos.

How much did the Xbox sell in China and how does that compare to past China launches?

Outside of its launch holiday, I think this is the first time Xbox Series has pulled ahead of PS4 in all regions?

Pretty sure. Xbox Series has obviously done a lot better since launch than PS4 in North America. That goes without saying. The PS4 is over 7 years old at this point and the USA is Xbox's largest market.

But as myself and others have said, Xbox usually gets steamrolled by old and new consoles from other brands (PlayStation, Nintendo) in Japan because Xbox is pretty much a nonfactor there.

However, the Xbox Series has better momentum in Japan at the moment than the Xbox One had. It's already about halfway to the Xbox One's lifetime sales in Japan. Xbox claims Japan is their fastest growing market right now thanks to Game Pass and other Xbox services across devices and the Xbox Series.

The Xbox Series S seems to be hitting it off with Japanese consumers. It seems like they enjoy the small, minimalist design. And of course the low price is great too. Now I'd imagine their not the fondest of it being digital-only (a sentiment shared by many regions) but it seems to be a worthy trade-off.

I think the Xbox Series S/X can match the lifetime sales of the original Xbox in Japan (0.53 million), possibly exceed them. However, matching or exceeding the Xbox 360's sales in Japan (1.66 million) is going to be a tall order. The Xbox 360 did the best out of Xbox consoles in Japan due to its headstart over the PS3 and Wii, as well as its Japanese software (true exclusives, timed exclusives, and multiplats). I think Microsoft is really going to have to push Game Pass and get even more Japanese software support if they hope to continue their momentum.

That's interesting; I guess while Xbox will almost certainly never be a competitive force in Japan, it would be cool to see it potential rise above being a complete non-factor. I can see the S's low price and small/cute form factor especially being more to Japanese tastes than its predecessor.

Maybe the Xbox Series can sell 200k in Japan which is good growth from the Xbox One.

Storage cost is igsignificant. I cant belive anybody still makes that argument. If any company wanted to stockpile anything it would cost next to nothing.specially since these companies already have their own where houses all over the world.

Now the missed sales is definetly a factor. Every unit they hold on to is a gamer that is not buying games for it and thats where all their money comes from. And selling it late can cost also because the games will be at lower price by then. Or the gamer could loose interest in said game and move on and its a full lost sale.

A company needs to weigh the benefits of said loses with the gains a huge Holliday will bring wich in my opinion is nothing more than pr. As the same amount of units will be sold. But you might loose on games being sold or bought at rwduced price. 

It's at about 50k after 7 months, so unless it has hobbit-like legs it should comfortably exceed 200k.

Demand is a lot higher this time around, no stock unsold for months like during last gen, but the xbox was also at about 50k after 7 months and it took 1 slim rerelease and a mid gen refresh to reach 120k or so. 

So that had hobbit-like legs, not seeing it happening again as demand is much higher (and xbox JP is pushing it a lot more) this time around at least.