I believe they are from the "YiGuanDao", definitely not
recognised as a true Buddhist community. They were call
"YaDanJiao", "BaiLianJiao" and other names in the past. They
believe that "Lao Mu" now holds the heavenly plate, which was taken
from the Buddha.
It is usually white and they are very strict with vegetarian food,
except for the egg part. If you visit them in temple or family
groups, you will be asked for a donation which is compulsary. And
when you join them, you need to make a swear with your life and
will be given a secret code - "Wu Zi Zhen Yan".
It is highly probably that it evolve from politics, at the time of
"Fan Qing Fu Ming" period in China. With a mission to recruit
members fast to revive the "Ming" dynastic. Slowing and over time,
it evolve into "YiGuanDao".
