They don’t have a single secret aircraft they are hiding. Nope not a single one.
They have several.
True. Analysis of those recent sightings (theaviationist.com did a good one) showed two distinctly different planforms.
And there have been rumors for years that the YF-23 (ATF competator that lost to the F-22) was developed and put into limited production as an F-117 replacement in the F-111 interdiction/medium bomber class.