From the Bottom Escapes section of BJJ Foundations with Cal MacDonald and Stephan Kesting https://www.grapplearts.com/bjj-foundations/

There are many techniques you can use to escape the knee ride (aka knee mount or knee on belly) in jiu-jitsu, but this is a high percentage one that leads you directly into some very dominant leglock positions like the backside 50/50 and the 411. Taught by Rob Biernacki, the creator of Modern Leglock Formula and Cutting Edge Leglocks – check out these instructionals so that you can tap out a LOT more people and finally become comfortable playing the leglock game: https://www.grapplearts.com/the-ultimate-leglock-sale