You can get more than one bid at my school during informal rush. However, at my school you generally have 24 hours to accept or decline your bid. You may want to think about that in case that is how it works at your school, too. You should probably kind of have in mind who you want to join because you may have to make a quick decision without a chance to see another group. Good Luck with your rush.
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I am who I am.
Those who matter don't mind,
Those who mind don't matter.