Looking at it, if we assume that Gen VI's primary pair will come out in Japan on 15th September 2013 (the second week of September, like most main series game), then that leaves another 70 episodes. Now, there could be another 50+ episode gap between Gyms 7 and 8 like there was in Sinnoh, or we could see an after Pokémon League arc in Unova. For example, if Black 2/White 2 introduces a Battle Frontier, then Ash,
Iris and Cilan could travel around Eastern Unova (with the facilities spread around Lacunosa Town, Undella Town etc) or there could be a short arc where they travel to a new area that B2W2 introduces.
Considering how many rivals we have in Best Wishes, I do hope that the Pokémon League is longer than the average 8 episodes though.
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