Summer may be in full swing, but back-to-school season for some marketers began long ago—in some cases before students even closed last year’s textbooks. Campaigns from Office Depot and Lands’ End, for example, have already been running for weeks, and more brands are expected to push out campaigns later this week. Compare that to 2016, when back-to-school TV commercials did not begin airing until mid-July.

“As soon as you’re past Fourth of July, you’ll see more brands and retailers talk about back-to-school, which I think is still early,” said Scott Madden, director of empathy at Boston-based advertising agency Connelly Partners. “It’s reached the tipping point where the commercialization and reliance on big data tells them the earlier they get to market, the more likely those shopping in that timeframe will spend more.”

Not necessarily, though. Though the $75.8 billion shopping season is the second-biggest (after holiday) for retailers, the bulk of spending occurs in late July through mid-August, according to ad tech company MediaMath. The company expects this year to be no different from last year, when consumers researched products in early summer but didn’t pull the trigger on buys until closer to the start of the school year.

“Consumers are spending a lot more time in their research and purchase-decision phases, and most of that is done online,” said Laura Carrier, VP-account lead and measurement at MediaMath. She noted that retailers are investing more heavily in awareness-generating marketing, by putting school products on blogs, in educational videos, on social media, or easily accessible on websites, to attract customers looking for inspiration. “Retailers are starting to make the information available earlier—it’s an inspirational fund versus a push to consumer.”

For Office Depot, which rolled out a new brand positioning and campaign on June 25, compared with July 16 last year, the early start is a way of getting top of mind with consumers.

“We’re building awareness early so that when we hit prime back-to-school season in late July, early August, we’ve got that nice ramp of awareness,” said Diane Nicks, senior VP-marketing at Boca Raton, Florida-based Office Depot.

Of course, early efforts could backfire. Some consumers—parents in particular—may not want to hear about back-to-school so soon, with the fatigue of last year’s slog still fresh in their minds. Lands’ End bore the brunt of the ire when it mailed fall catalogs to customers in mid-June. “WTF, @LandsEnd? We got your #backtoschool catalog in the mail. Our kids still have two weeks of school left this year! #fail #marketing,” tweeted Greg Magin.