Snapshot block = 3,105,500
Snapshot and pre-launch opt-in closes = March 12, 2021
Symbol mainnet launch = March 15, 2021

https://twitter.com/NEMofficial/status/1364168188431392768

1 XEM = 1 XEM + 1 XYM

  =  +

combine the two vectors...
magnitude of resultant force is

  + =

It's just HODL and simple physics.