A clean-water leak that sits for two days can degrade to Category 2, and that changes the scope. That is the practical reason speed on day one matters.
Class matters just as much for the schedule. A Class 1 loss in one bathroom may dry in a couple of days, while Class 4 losses in hardwood, plaster or concrete need specialty setups and more time. Your restorer should spell out both ratings plainly and record them in the project file.
Keeping Three Parties Aligned
A good project lead updates the adjuster, chases phase approvals and gives you a realistic move-back date. Ask at the first visit who that person is and how often you will hear from them. If the answer is vague, that is worth noting.