Unfortunately, the schedule of "international pokemon" is very unstable and hard to know in advance (even for Japanese). It fixes only 1 month in advance and often changes afterward. Perhaps this is why ANA pulled it. There exists special customer service on a special phone number in Japan for asking questions about pokemon flights but even they refuse to reveal the schedule. The only way I can think of is to ask ANA where JA8962 is flying as often as possible...