Boom’s web site makes the puzzling claim that there won’t be any more flights of XB-1 despite not reaching even the reduced target of the first Boom airliner concept.
Boom does need to test its Symphony engine somehow, I hope it also is ready for first Overture airliner to need tweaking, not get caught as many aircraft designs have - Boeing 787 for example, first few produced could not be refurbished and sold to airliners. Albeit an unusually badly led project for Boeing compared to B767 and B777.