I dson't own a FFC pro but I do use S3D : I usually do something similar to what Curious Aardvark pointed at.

Use M140 and M104 to set heat bed and extruders temps
And AFTER, you put the lines for M190 and M109 which force to wait until temp is stabilised.

Works for my printer but as the others pointed out : it works only if the current output allows it...