During this period of time each June, TV stations anxiously await the demographic shares they will be selling for the remainder of the year.
RatingBook.com clients know I check their MediaOffice servers several times a day during their window of data arrival.. the sooner I start, the sooner your sales team can get to work.
While I do have access to Nielsen's release dates, my experience over the past 16 years of RD work in metered markets tells me not to count the chickens before they hatch; good intent means little if the data isn't accessible to the end user.
BTW, the Nielsen VIP telephone hotline, which used to be updated each day sweeps data was shipped, hasn't been updated for more than 340 days. I'm sure there's a reason.