Speaking as a venue who receives the RFPs, I believe you can simply edit or adjust your RFP. It you have received responses already, you can still update the dates, and it will show on our side saying "RFP no longer matches proposal" or something along those lines. It will also include a comparison of the changes. I've seen it before and it's fairly straightforward on my end... I don't know the exact steps though as I don't submit RFPs, I only receive and respond.
Alternatively, if you have received responses, you can contact the venues directly.
Hope that helps!
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Lori Fitzgerald
Sales Manager
DoubleTree by Hilton KingstonCanada
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