We have the big sister revealed the night of pledging (a day or two after bid day). Since our campus and chapter is small, we are able to get to know the PNMs fairly well during recruitment and even more during bid day. I like that we assign them so early because every week from pledging to initiation the big/little pair does something together with a small group of other sisters that were not assigned littles.

One thing to make sure of -- one year our New Member Chair just assigned the littles/bigs the night of pledging without talking to the assigned bigs first. This was a disaster for one big/little pair, since the big really didn't like the little at all and hadn't even supported letting her into the chapter. This rift was a problem in the chapter for the next 3 years since eventually the big and little got into a big fight and the little felt betrayed -- like she was screwed out of a "real" big. Lesson: ALWAYS talk to the big before you assign them a little. You never know how someone might feel about it until you ask.

At my chapter, you got an Alpha sister on bid day, an Epsilon sister a week later, and a Phi sister (your big) a week after that. I'm pretty sure they still do it that way. The new member period is 6-8 weeks, so you have an "official big" for most of your NM period, but before that, you have two different "temporary bigs" who give you little gifts, take you out for coffee/ice cream, and basically make you feel welcome and make sure you meet sisters you might not have met during recruitment.

The assignment of big/little is a national policy for each sorority. Every 2 years, a sorority holds a convention of voting delegates to review policies, vote on amendments, etc. Collegiate chapters and alumnae associations send a delegate to the convention to represent them and vote on their interests.

It's hard to say which is better: to get your big sister on Bid Day or to wait a few weeks, because it depends on the sorority's intention in waiting or not waiting to assign them. It is also hard to say which is better because you can only be a member of one sorority and you only have your own experience to draw from.

My chapter waits until the week leading up to initiation to have big/little week and revealing. In the meantime though, the girls get a Bid Day Buddy, then a couple weeks later, a Sailboat Sis, and then a Violet Sis before big/little assignments are done via mutual selection. It could've been someone you've paired with previously, or someone you've gotten to know on your own. I liked that my Big was someone I was already very close to, but in the meantime had three different people to go to.

At my sorority we called the bigs that we got on bid day our kite sisters.

Kappa's Key Sisters are big sisters. They're not "Bid Day buddies" or temporary big sisters of any kind. I got my Key/big on the night of my pledging.

In my chapter, we still did reveals. We just did them sooner than any of the other chapters on my campus.

It was explained to me this way: Your best friend is going to be your best friend whether she's your big or not. Your big is just an extra resource, an extra connection. And really, from a survey of sorority women I know, Kappa and those groups who wait to assign bigs have the same proportion of people whose big is their best friend, people who are closer to their big grand-sis, people who are closer to someone completely outside their family, and people who (sad, but true) hate their big.

In any event, I lucked out and my Key Sister is my best friend.

OP-You sure pick rather odd threads to ask rather odd questions.
Trying to write a paper or something??