I don't know about notifications...
You can go here:
F1, IndyCar on NBC Sports schedule - Motor sports- NBC Sports
Or, you can listen to the commercials, or the announcers, as typically they will announce the broadcast times/stations for the next race when wrapping up the current race.
Or, realize this has been going on for years (Speed did it with Fox) and just program your machine to record anything F1 related on both NBC and NBC Sports.
HINT
This is going to happen again
This traditionally happens with the Canada race.
The Canada race is the next race.