according to japs
in order to promote from sapphire to diamond you must
1. win at least 13 games in sapphire
2. win 13 of the last 20 games you played
once you hit 13/20 games won as your last 20 games, you will automatically promote
if you don't win at least 11 of your last 20 matches in diamond, you demote to sapphire

is there any validity to this data? or did this guy just pull it out of his ass?