Go to pollstar.com and search for artist "Van Halen" tour dates.Now it will come up with no dates now being shown on the books but will give you a registration prompt(no charge of course) to be notified when VH announces tour dates.
Now speaking from experience here,pollstar posts dates way the fuck in advance,possible/probably before ANY announcements are made on behalf of VH/ with Dave.
As soon as even one date and venue is set,promoters have pollstar post it for ticket buyouts with radio stations and such.
I have seen concert dates posted for BIG bands posted well before any tour schedule was ever announced on their behalf.
Pearl Jam,Ozzfest,Metallica etc.etc.
Just a heads up that might give us a day or two jump on any "announcement"

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"I Got Myself a Brand New Oakland Scarf right here I say"