Spray Foam Insulation in Attic

Hi all - I am having the insulation in my second floor attic redone shortly. The current insulation is BAD (old, news paper pike material).

The work to be done is to first remove the old insulation. Then, polyurethane spray will be used to seal the bottom layer, to then be covered by 15” of loose fiberglass to increase the insulation levels to R-60.

My big question: how long should my family and I be out of the house after the work is completed? I have heard the curing process can take considerably longer than just a few hours, so I’m wondering if we should be out of the house for several days? We have two young children and a cat that live in the bedrooms under the attic.

For reference, the 1000sqft attic is unconditioned. There is an air handler for a heat pump in the attic but the space itself is not conditioned. The attic is accessed through a hatch door that will be weather stripped.

The company performing the work simply suggests not being home while the work is done, but I feel like the internet at large recommends a slightly safer approach — any thoughts?