Yesterday I was at CeBIT2017 in Hanover, Germany.
I there talked to Yuneec staff about the "new" Accelerometer Calibration method menitioned in the YTH manual v1.2.
They told me, that the new hovering calibration is ment seriously and has a lot of advantages, because the calibaration adopts better to "in flight" conditions than the "on ground" calibration.
I also met the german YouTuber "Fan Tho Mass" at CeBit2017 and asked him about the "new method". He told me that he just posted a video about the "beginners on ground" and "advanced users hovering" acceleromater calibration:
("advanced users hovering" acceleromater calibration starts at 3m29s or 6m12s. You may use subtitles and auto translation.)
"Fan Tho Mass" and Yuneec staff told me that is important to know that accelerometer calibration generally turns off GPS, so that the hovering has to be controlled manually. Stick inputs by the user (to keep the position manually) are "subtracted" by the calibration process so that the result is expected to be "stable".
As it is right now not too windy outside I will give this method a first try...