Two questions regarding dispatch/JET

I have been told by some friends that they have received emails from their dispatch about being transferred to new locations – They did NOT request this. I specifically have requested a transfer and was told it would be very likely to happen due to issues at my school. Is there a general timing for when I will be emailed about this? Considering I finish at my position in exactly two weeks today, it feels late to not have been told anything.

Have people left their dispatch to move back home, simply to try to apply for JET in that same year? The only thoughts I can find on this matter are people saying the usual "There is no point leaving an ALT position to try for another one". To me the pay, benefits and the extended period of staying in Japan seem worth it.