Lead Times, Delivery and the Day the Stone Arrives

Homeowners tend to hear one number: two weeks. That number usually refers to fabrication alone, and fabrication is the middle of five stages. Adding the others gives a calendar you can actually plan a kitchen around, including the stretch with no sink.
The Realistic Chain

Selection and quote come first and depend on you. Then the cabinets have to be finished and fixed, which is somebody else's schedule. Then template, which is a single appointment but sits in a queue. Then fabrication, commonly one to two weeks and longer for mitred edges, waterfalls or unusual materials. Then delivery and installation, which is usually one day. A backsplash or a plumber visit can follow after that.
From template to install, ten to fifteen working days is a normal expectation for stock material with a straightforward layout. Special order material adds however long the distributor takes, and that is the number worth pinning down in writing.
What Adds Time Without Anyone Announcing It

Material not held locally has to be freighted. A slab that breaks in fabrication resets that portion of the schedule and, if the bundle is gone, resets the selection too. A sink that arrives late blocks template. A layout change after template restarts fabrication. Holiday weeks compress shop capacity in both directions, before and after.
Preparing for Install Day
Clear the path from the street to the kitchen and take a door off if the route is tight. Empty the base cabinets so the crew can work inside them. Remove anything fragile from adjacent walls, because full slabs are carried vertically and corners get close to things. Plan to have the kitchen unusable for the day and the sink unusable overnight, since most adhesives want a cure period before the plumbing is reconnected.
Have somebody present who can make a decision. Occasionally the crew will find something that needs a call: a cabinet that needs reinforcement, a wall that needs more scribe than expected, or a seam that would sit better twelve inches from where the drawing put it. Those are quick conversations in person and a lost day over voicemail.
Before They Leave
Walk the counters with the lead installer while they are still there. Run a hand over each seam, look along the run at eye level for a dip, check the overhang is even, and confirm the sink reveal matches what was ordered. Look at the caulk line at the wall. Snags are fixable in the first ten minutes and awkward once the truck has gone, and every crew would rather sort it now than come back.