Yes, that's true. I was thinking about Brighton's experiences but you're quite right: top 2 in Div 2, top 1 in the other divisions.
It's before my time but what happened if two northern teams went down? Would one go in Div 3 South or would both go in Div 3 North and one of the more midland...
That's not right either, it used to be just one team from each division who got promoted -one from Div 3 South, one from Div 3 North) It only became two in 1958/59. So it was only for about 15 years that the top two went up