grub questions

first off i want to ask will the next version of mageia be able to be upgraded from mageia
2. if not then does anybody think mageia 4 will be able to upgrade from mageia 3.
and the next question is why did mageia use grub 1 instead of grub 2 in the first place.
2. if not then does anybody think mageia 4 will be able to upgrade from mageia 3.
and the next question is why did mageia use grub 1 instead of grub 2 in the first place.