Sales aren't all that important, series with good ToC placement outlast higher sellers every year. Especially if sales drop after v1 like what may be happening to Yozakura, sales dropping this early is not a good sign.
Chances are the next batch will be the Burn the Witch one in Summer, and I imagine that'll be a good 12 issues minimum from now (possibly longer considering how many series we've had recently and depending on how the current situation in Japan goes) which is plenty is time to see if any series stays in dead last or not and if a new series ends up in dead last for 3+ straight months chances are it'll be gone, whether it sells okay or not.
As it is, Agravity Boys has done pretty badly in the ToC so far and doesn't have much hope if it keeps up, and Yozakura's also pretty shaky. There's no saying whether either will survive past summer as of yet (I think it really depends on if they get other proper hits).