AST SpaceMobile is making progress and building a business, but at a cost.I hate to say I told you so (but I did). And just as I forewarned back in September, AST SpaceMobile (ASTS 11.15%) stock has decided to dilute its investors.Again.On Thursday last week, AST management announced plans to float $400 million worth of convertible senior notes due 2032 (that's debt, convertible into stock) in a private offering to qualified institutional investors. The company explained that these notes will pay 4.25% inte ...