This is covered by the Tips and notes and by general materials about the T/V distinction https://en.wikipedia.org/wiki/T%E2%80%93V_distinction
ty - informal singular
vy - formal singular, plural
In southern English, the plural you can be expressed with "you-all" or "y'all".
If the group consists of more than three and you are referring to everyone in the group, it can be "all y'all".
Y'all may refer to an indefinite set of members of a group, but all y'all definitively includes everyone in the group
I'm joking. Somewhat.