The fate of the National Flood Insurance Program is hanging in the balance once again, and local experts are getting fed up with the uncertainty. “This is extremely, extremely frustrating,” Joe Rossi, chairman of the Massachusetts Coastal Coalition, said Wednesday. “It’s not just frustrating for the residents we serve, or for me as an agent or advocate, but it’s frustrating for everyone because it never ends.” The flood insurance program expired last Friday, Nov. 30 and lapsed for about 11 hours before President Donald Trump signed a bill that included a seven-day extension, realigning the program with the larger government spending bill deadline facing Congress this Friday.