The next set of Lost Art Promos have been revealed and it's a big reveal. The Anniversary Dark Magician Girl was truly a "Lost Art" as the creator of Yu-Gi-Oh!, Kazuki Takahashi, placed heavy restrictions on any alterations to the cards printed in Anniversary Pack. We were never able to get a TCG version with this art, but we will soon.
Release dates on the next set of Lost Arts have not be announced as more details will be revealed. Remember that even when the duration is announced, we won't know what the promo it is for the month until we get it, so keep an eye on our Media Channels.