Nakajima Kento, Kikuchi Fuma, and Sato Shori of Sexy Zone have been announced as the supporters for the 2015 FIVB Volleyball World Cup (source). Yes, that does have the implications that you think it has-- they're apparently in the place of what should have been the new 2015 volleyball debut.
In case this isn't something that's common knowledge, just a little history on the volleyball debut: It's a tradition that started in 1995 with V6 and has happened every four years since then. The FIVB World Cup is a big deal Olympics qualifier volleyball event that happens in Japan every four years, and since 1995, Johnny's has been supplying the popular media "support group" and song for this event. V6 was followed by Arashi (1999), then NEWS (2003), then Hey! Say! JUMP (2007), and finally Sexy Zone (2011).
Up until this year, the FIVB Volleyball World Cup has always happened in November. This means that all the volleyball debuts have been announced in September and their debut single dropped in November. For that reason, we celebrate these groups' anniversary in September even though their debut date is actually in November. I don't really understand this tradition (debut is debut imho), but either way, end of September and mid November are the key time periods in (almost) every volleyball debut. This is something that's gone on for the past 20 years now.
However, this year, for reasons unknown to me, the FIVB Volleyball World Cup has been pushed up to August. That would mean, for a new group to be supporting it, the debut announcement would have to happen at the end of June and their debut would be in August. That's a whole three months earlier than every single volleyball debut for the past 20 years.
But for reasons also unknown to me, instead, the front three members of Sexy Zone have been announced as the supporters of this year's world cup. This breaks with 20 years of Johnny's tradition and is, for a variety of reasons, pretty surprising and alarming to me. First of all, Johnny's tradition is pretty good. I like Johnny's for a reason-- that it's Johnny's. Them changing their formulas and breaking long-standing, important traditions is not something that particularly comforts me or makes me happy. Second, the volleyball debut is a big deal, and an important chance for juniors. Not knowing when it will happen or if it will happen at all is highly concerning. And of course, third, all those Sexy Zone-related issues. But that's another matter for another post that I am almost certainly not going to make.
Still, perhaps it's a personal flaw or perhaps it's because we all want to find some sense of security in the craziness that is Johnny's, but it's all I can do to give a few options of what may happen from here. Note that in the past 20 years, there have been some changes in the pattern of the volleyball debut, so this does not necessarily signify the end of an important tradition.
Therefore, with no further ado, my hypotheses for what might happen:
① A support group may be announced in June at Johnny's West's Kobe shows (for a Julie group) or at a yet-unannounced Sexy Zone, Kis-My-Ft2, or ABC-Z performance in June (for an Iijima group). Having two supporters, one from a previous volleyball unit, is not unheard of; Sakurai Sho was a supporter along with Hey! Say! JUMP in 2007.
↳ ⓐ Therefore, a new group may debut on an expedited timeline of June → August and present along with the Sexy Zone members, perhaps with Sexy Zone's presence to draw interest for the new group.
↳ ⓑ An alternate theory is that, like NEWS, the new group may be a Junior unit, perhaps presented as secondary backers to the Sexy Zone members. NEWS so far is the only volleyball support group that was considered a Junior unit at the time of the FIVB World Cup, but that doesn't necessarily rule out something similar happening again, with a debut following in the year after.
↳ ⓒ A third option is that Sexy Zone's participation may be an out-and-out lie, as with Johnny's strange fake announcement of ABC-xyZ back in 2011.
② The agency may be choosing to keep the new group on the same timeline, September → November, regardless of support opportunities. The FIVB World Cup itself has little to do with the debut besides it being the supposed reason; Johnny's debuts non-volleyball groups with equal frequency, so there's no actual legitimate necessity for the "volleyball debut" to actually be a debut with relation to volleyball. It may still follow the same formula (the timeline, the age gap, the "fresh" members… see my post here, and then the following two here and here for more details) but simply be unrelated to this year's World Cup.
③ The agency may choose to have the group support the 2016 summer Olympics instead, either having them debut in the same September → November time frame, or perhaps pushing back the debut into 2016. This would be odd to me, but I don't necessarily think it's impossible. It might also fall into the same category as option ②, if the group were to debut in November and then just happen to do the support for the Olympics.
④ Perhaps there will be no volleyball debut at all, and Johnny's will, once again, completely thwart my continued attempts to understand it.
Frankly, I don't see how the agency could possibly benefit from breaking with tradition. The volleyball unit is a carefully and very intelligently concocted formula: it creates interest from a wide range of fans with members with a wide age spectrum, it draws the support of Junior fans while still keeping them paying for Junior events as well by splitting up popular Junior units and leaving some popular Juniors behind to continue to head up the Junior fandom, and it captivates fans for a long period of time to watch the completely new group come together, form a bond, and grow. This method has been a great success in the past (considering Arashi is a volleyball unit), and is, in my opinion, an integral part of contemporary Johnny's as a subcategory of popular entertainment. I really can't imagine how not having such a debut at all could be seen as a positive from a marketing or image-branding standpoint.
But at the end of the day, I don't work for Johnny's, and I can't really make any statements with certainty. So for the time being, I'm just going to leave it with this and hope for the best.