There are two types of blocking of aircraft flight information:
1. The FAA Source level blocking blocks all aircraft information coming out of the FAA system and companies like FlightAware would not have access to information about flights blocked at that level.
2. The ASDI (Aircraft Situation Display to Industry) Subscriber level blocking of an aircraft means the FAA transmits the data to vendors like FlightAware, but FlightAware blocks that information to the public but can offer it to the owner/operator.
If your N-number is blocked at the ASDI Subscriber level, then all you need to do to get Expected Flight Notifications is to link your ForeFlight account with your FlightAware account. To do this, please see the following article:
After linking your accounts, you will get your Expected Route Notifications.
If your N-number is blocked at the FAA Source level, then you will need to change the blocking to be at the ASDI Subscriber level and then link your ForeFlight account to your FlightAware account as described above.
If needed, you can contact the FAA and ask that the blocking of your aircraft be changed to the ASDI Subscriber level. They update their block list on the first Thursday of each month.