I thought this might be relevant to many: GPS reception may be unavailable or unreliable over a large portion of the southeastern states and the Caribbean during offshore military exercises scheduled between January 16 and 24.
The FAA has posted a flight advisory for the exercises that will require jamming of GPS signals for periods of several hours each day of the event. Navigation guidance, ADS-B, and other services associated with GPS could be affected for up to 400 nautical miles at Flight Level 400, down to a radius of 180 nm at 50 feet above the ground. https://www.aopa.org/news-and-media/all-news/2020/january/14/gps-jamming-expected-in-southeast-during-military-exercise?fbclid=IwAR3VMlOdPUFTHuoujPShqt3qhEIe3mAhSS-pU5M56CQ14zNX8qSBqWa5WcI Regards Marshall Eubanks