Wow, this is scary. It reminds me of the history of monetary economics in the US during the 19th century, a period known for "wild cat" banks and a system where any bank could print their own private currency. In that system, currency was discounted the further away it was physically from the bank which issued it. The system was divided between "city banks" and "country banks." The more remote the location, the less up-to-date information was available about the health of distant banks, and so the more distant currencies were discounted more heavily.
The modern crypto wild west version of this is going to end in a result of going from "getting $0.99+ on the dollar is probably good enough for a lot of people" can turn into "getting 0.01+ on the dollar is as good as it gets" within minutes, if and when there is a run on crypto stablecoins.
The main point I was trying to make was that people trying to make a buck off of the USDC depeg didn't need to wait until Monday morning. So I didn't think Monday morning would be particularly significant in that particular regard.