User blog comment:Trainer Micah/Pokemon UltraSun/UltraMoon prediction's 4 Anime/@comment-26573805-20171003220118/@comment-26573805-20171007191611

Actually, we know from several past trailers, dub title reveal dates, iTunes description for SM Volume 3, the short gap at the end of dub season 18, etc. that the production of an episode's English dub begins before the episode airs in Japan.

The YouTube uploads aren't official, and are quite illegal - the only official uploads are those by the broadcaster (on watchdisneyxd.go.com and its app) or those on Google Play, iTunes, and Amazon Video. In Japan, the official uploads are done by on demand providers like Hulu and Netflix, and through the production companies' library on Amazon Prime, where every series and every episode is listed (the Mega Evolution and Mewtwo Saga are listed in the episode numbers as they are episodes that follow the plot of the main series) - every episode is available except for Cyber Soldier Porygon (Electric Soldier Porygon is a commonly parroted mistranslation originating from the dark days before Google Translate even existed, or before westerners had online methods of learning Japanese, the mistranslation has been overrated for little more than a decade, 電脳 means "cyberspace", 電 by itself is "electric", however 電脳 is the one in use and then 戦士 for soldier/warrior/combatant, the title spelled in kanji itself would be 電脳戦士ポリゴン). Those torrenters cut out advertisements, though I know for sure during the WTP of the Porygon episode, they showed a Nintendo 64 Yoshi's Story advertisement, not surprising as it was aired 5 days before that game's release.

So yes, they're essentially produced in 6 months from conception to completion, and the American dubbers localize it in a short 3-4 months time frame, usually beginning a month before the Japanese airing. Although for BW023/BW024, as TPCi in America has access to The Pokémon Company's complete library of produced episodes, Tom Wayland has confirmed seeing those skipped episodes ("The Rocket Gang VS the Plasma Gang"), just that TPCi opted out of dubbing them due to being seemingly permanently skipped in the country of origin. If you're curious 前編 (zenpen) actually means "former part" and 後編 (kouhen) means "latter part", but English speakers generally take it as "Part 1" and "Part 2" for Pokemon.

Back in the dark days before rental DVD's, and all these on demand services existed, and before there were channels rerunning the show (Kids Station, BS Japan), the only way to watch an episode legally and legitimately was to catch its original airing or to tape the airing if you want to re-watch an episode. In America, there's more generous rerunning on the same network that airs news episodes, rather than the network sending copies to the rerun networks and having them air it instead.

I'm not one who prefers the dub over the original for various reasons: etc.
 * Short 30 second "theme songs" that the original has way better opening/ending theme songs for
 * The voice acting is lacking.
 * Exclusion of episodes on the basis of boredom to dub them, such as DP192/DP193, BW145/BW146, XY142, the original being way more complete than the American dub, which functions as an essential rerun copy of what's already released, and it releases months after its official main release. The original has ALL the episodes, the dub just dubs the episodes they feel necessary to make so much money on the TV views and home/digital video releases. Likewise, IL035 is not a banned episode and airs normally, IL038 is permanently banned and will never air again from here until the end of the world (I'm pretty sure they're blocking every release of it, whether it's broadcasting, home video, digital video, licensing out, etc., I think it's still available in circulation internally and that it wasn't destroyed, just will never air again, the only thing I can see is the master or "official" digital copy getting leaked or sold online somewhere someday, but that's it). It's just that if 4Kids were dubbing a 13 episode series that involves excessive gun usage, they would have problems but will certainly in the end find ways to change it - however for Pocket Monsters, it's a series that shows no sign of stopping and skipping one episode does not do that much harm, as they will never run out of material to dub.
 * Being bound by American television censors (IL034 and Taro making a joke about Kasumi's breasts, he explicitly says おっぱい飲んでいいか, meaning, literally Can I swallow on your breasts?, this is seen as inappropriate and offensive in America, Tommy in the dub said "are you people or Pokémon?" and Misty replied saying "I'm a person, you creep!"), IL035 being skipped entirely (while being perfectly acceptable to air normally in Asia), Rougela having a redesign over a controversy specific to over in the US, IL018's mass censorship in its dub that only aired twice and then once again disappearing from rotation and never included in any dub season, etc.
 * Tampering with the show's Japanese origin and heritage (removing Japanese language text, desperately trying to "Americanize" it out of its true culture, even getting the writers to stop using their country's culture in the show, if I was a writer of an anime show being adapted in America, I would literally troll the dubbers with Japanese text everywhere in every episode)