Here is how Revolut executes orders below market price against their customers.
I placed STOP ORDER in Revolut app around 15:57. Order executed immediately, and 101 EUR below market price at that time. (Or any time after that) Order executed at 15:58 Local time or 12:58 UTC. My order executed with price of 26328. Actual price have not reached level of 26328 even 1h 50 min earlier or few hours later, in fact it BTC still trades way above that level.