Is it possible to delay opening calendar to Airbnb & VRBO?

We would like to give our past guests first dibs when we open our calendar up in the future and encourage them to book direct on our OR website before it is open to everyone else on Airbnb & VRBO....is this possible to do?

Sure, you can set a different booking window in the API settings specifically for Vrbo and Airbnb, that is shorter than the regular one in your Property Rules.