Max Number in a Party Need Help!!!!!!!!!!!!!

I tryed to use the search and did not find what I was looking for so hear it go's. What is the max you can have in a party in the first part of the game. Can you make 2 partys 2 and 2 and then add them to have 4 or what as me and 3 of my friends have the game and last night when 3 tryed to join it would not let us do it.

Thanks for the help.

2 pre-searing, 4 after

Except for GvG which is 8

and im sure i had a max of 6 when i reached post-searing yaks bend in the beta...

yah it goes up once you get further out. By end of beta I was in a party of 6 pretty much the whole time in those far areas.