So the 'Weekly Quest' didn't reset until the 30 day login calendar reset. Even better one of the new quests that rewards 50 diamonds is to use 20 energy drinks, of which the cheapest is 10, so you need to spend 200 diamonds to get 50. I mean you get some drinks for free from the login calendar but only on 2 days of the 30 so nowhere near enough. Luckily diamonds don't seem very important. All current girls are at the highest level currently available with a couple of them maxed out towards the last tier whenever it launches. I do recommend saving all free gacha tickets until you have a girl that requires the special items that only come from there to give yourself more chances. I have a bunch saved now in case the last steps to unlock the highest tier require them again.