A couple of point re preconditioning:
When you precondition the Tesla Model Y when the battery is cold, i.e. below 4C (39F) the amount of battery warming that will be performed is not enough to enable full regenerative braking once you start to drive. Tesla has provided a setting under Pedals & Steering that will automatically blend the friction brakes with regenerative braking when regenerative braking is reduced or unavailable. Enable this setting and you will never experience a reduction in braking force when you lift your foot from the accelerator pedal when regenerative braking is reduced or unavailable.
As battery warming while preconditioning before driving is now limited the preconditioning function is primarily used to warm the passenger cabin. Unless the outside air temperature is well below 0C (32 F) you will only need to precondition for 10 minutes or less to bring the passenger cabin to your desired temperature. Set the heated (front) seats and steering wheel heater to Auto and the Tesla Model Y will automatically warm these during preconditioning.
If plugged in while preconditioning this will reduce the amount of energy that is drawn from the battery for the heat pump to operate, etc. while preconditioning. Battery warming will use stator heating and draws up to 3.5kW per drive unit stator (front and rear.) If you normally charge at 48A or 40A then most if not all of the power needed for preconditioning will come from the grid. If you normally charge at one of the lower amperage rates for Level 2 (240V charging) then some of the power used for preconditioning will be drawn from the high voltage battery. Preconditioning while plugged in using Level 1 charging (120V) will only provide a small percentage of the power used to precondition the Tesla Model Y.
In my experience preconditioning in the A.M. uses ~2% of the battery (In winter I generally precondition via the Tesla app before driving for ~8 minutes.) The Tesla app will notify you when the desired cabin temperature has been reached. I estimate it costs $0.10 to $0.15 to precondition my Model Y in the A.M. (in winter the temperature inside my unheated garage rarely falls below 0C (32F) but frequently does hover around that temperature early in the A.M. in the months of December, January and February.)
Special Use Case: when there is snow and ice on the Telsa vehicle, use the Defrost Vehicle function within the Tesla app as this setting will quickly begin warming the passenger cabin while also defrosting all of the windows, cameras, side mirrors, and charge port. Also, the rear hatch glass defroster will be turned on and the windshield wiper resting area of the windshield will be heated. (If there has been a decent snowfall you should brush any snow off the the Tesla vehicle (especially the roof, hood, lights and turn signals before starting to drive. Note that the LED lights don't generate enough heat to melt snow and ice from the headlights, tail lights, etc.