Hi Phil, nice to e-meet you! :)
This will depend of your needs. If you need to make a budget for each of your webinars, I would recommend you to make it as an event for each one and not all in one event. But if you don't manage your budgets on Cvent and you are only looking for the Agenda/Sessions feature, I guess you can create different sessions as webinars with different dates (that you can modify afterwards). If your webinars happen within an entire year, then you will need to set your event dates as (01/01/202X - 12/31/202X). Both ways are possible, it's just a matter of what you need from Cvent for each of your webinar.
Hope I could help a bit, let me know if you have further questions.
Have a nice day!
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Wim Behaegel
wim.behaegel@amexgbt.comParis, France
Tech & Digital Planner, MSD Account
AMERICAN EXPRESS GBT
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