>>58413710>>58421431Odds are, something similar to Eternatus will happen with Zygarde. We won't be able to catch Zygarde from raids, we'll probably be given just 1 (one) again, and raiding the different Zygarde forms will give you cells (while battling Mega Zygarde raids will give cells and mega energy).
So I wouldn't worry about doing routes honestly, that and the fact that if Mega Zygarde isn't launched next year (Kalos Tour) it will be launched in 50 years, so there's no need to worry about that either.