Hi Chelsey,
Thanks for your question!
You can create a virtual registration type and admission item and select what day you want it to open automatically. You can have them set up ahead of time so when your in-person capacity is reached, you can open up the virtual registration option.
You can also create a planner alert for when the capacity is reached so you get a triggered email notification of when this occurs.
Hope that helps!
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Sydney Langer
CSA
Cvent
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