Hide all extras tickets once main admission tickets are sold

HI,

We are using wp-events to manage admission to an Open Garden, whereby we limit the total number of people in any session e.g. 40 people. We also offer optional Picnic refreshments that should also be booked in advance.

Treating them as two independent tickets can mean that we could still have picnic tickets for sale when the main Adult tickets have all been sold.

Is there a way to mark the event as fully booked once all of the Admission tickets have been sold, even if there are optional picnic tickets remaining?

Thanks, Bob

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