Don't they make a blue pill for when things start to get soft?Well, to replace a sensor, the tire(s) need to be broken down from the wheel, remove old sensor, install new with a service kit. The shop will need to get the sensor out of sleep mode and upload the tpms info into the car's system.
Annoying, but at times those sensors detect a tire going soft and triggers the light before the operator is even aware of a problem