Think you're right they must've been buying it up. Would make sense to bid up the currency and not the stock market too, can only imagine how bad the bank runs would be if the ruble craters on top of all this.
0: https://markets.businessinsider.com/news/stocks/warren-buffe...
If Russians stop accepting rubles and use foreign currency for transactions, the Russian govt stockpile of rubles, and it's ability to print more rubles, becomes worthless. They will need foreign currency to pay people.
Well, given the sanctions they might as well burn these dollars/euros. So maybe it's not that bad to pump their currency rate here.
So, I think they can move their yuan freely to China still, but USD and Euros are harder to move (though not impossible?) in China