Yes, definitely make sure that you have no other possibilities. You'd hate to leave school only to find out that you could have stayed.
And if you're only 95% sure that you're going to transfer right now, I wouldn't announce anything to the entire chapter just yet.
If you do have to transfer, I would probably talk to the President and/or any advisors about your situation. From there, do what makes you feel comfortable. If I was in such a position, I would probably talk to the sisters I felt closest with, and then tell everyone at the end of a meeting (after it's been adjourned). And I would probably say something shortly after I found out I was leaving.
But again, it's essentially up to you as to how you want to deal with it.
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I believe in the values of friendship and fidelity to purpose
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