Mission failed

[Knick Of Time]

When ever I try to start the big score heist the mission automatically fails. Im at the part where all 3 characters meet inside the club and discuss how to hit the bank. Everytime when i start it the mission automatically fails saying thatthe security convoy reached the city. How do i fix this?

[Biggus Dickus]

i had the same problem
what i ended up doing was pressing retry untill it said skip
you have to do that about 3 - 4 times then youll be in the chopper
ik its not the most ideal way but it worked for me