What's happening in the market? What triggered this pump? Like I was thinking that btc is still struggling around $63 to $64k until this morning I want to make a payment, I kept refreshing by wallet.
What happened? is it related to the media hype man - Saylor or something about the clarity bill?
The FED started a buyback, as always it's Uncle Sam coughing or winking and the whole market goes crazy.
Anyhow, this is less exchange and more trading talk which nobody knows the answer, if we would have that knowledge, we would all be on our private islands now not caring a bit.

I'm not saying that it doesn't happen that someone enters BTC for a "time" and buys cheap, but these are mostly just lucky coincidences. Big players don't make decisions overnight, they are planned for a long time.
Big players can be wrecked too in minutes.
You would have to be not only an insider but two have known how everything goes in the last 6 months to guess this move, and if you would have been able to know these things, well then 20% up in 6-9 months since Q4 last years, well, it's not that much money!
Does this in anyway mean that when the reserve is low, fast mode is switched off?
Correct — that's exactly the mechanism. Low reserve
on a specific coin means Fast can't safely cover an instant payout for that pair, so it drops back to Chain until reserves are topped up.
Are you 100% sure about this mechanism triggering only for certain coins and not just one making it shut down completely?
I'm asking because, well, it seems like I've been so unlucky and hit only times when the entire fast exchange was down or completely working, I've never seen lately one pair working and one not being available.
Of course, I might have stumbled upon that 0.00001% coincidence rate but just checking, right now, all pairs are down not a single coin is available on fast.