To add, when the drop cue stops functioning you can continuously press weapon release and drop all your ordinance regardless of your position to the target.
Edit: After some additional testing regardless of cold / hot start on ground or flying start the bug surfaces. I tried changing SOI from HUD to TGP to FCR and sometimes the issue goes away and the fall cue works. I did also notice when your outside of the drop parameters you can almost guarantee drop ordinance over and over again as if it was CCIP. (Which I demonstrated at the end of the attached trk file.
F-16 CCRP Drop Cue Air Start.trk