Next saber banner

There will be a banner with only Saber Class to summon in September. Or you can wait for the banners before the next chapter (in 2 or 3 months usually) with some Saberfaces in the rate up like OG Saber, Saber Alter, Nero...

The next one should be when the first anniversary is released. For the first anniversary, they will probably do a daily summon focus of each singularity, where a few saber faces are thrown in there(Saber alter/Artoria in Fuyuki, Nero in Septem, Mordred in london)

I would save my quartz for Summer Artoria (Archer) not only do you get Artoria in a cute bikini, she is a top tier arts-type damage dealer.