If your intended output is video, I would suggest you just split your project into multiple FLAs and then combine the exported videos in Premiere.
A way to have a longer FLA is to wrap 16,000 frames into Movie Clips. Each Movie Clip occupies only one frame on the Main Timeline. In theory you can have 16,000 Movie Clips with 16,000 frames inside each of them.
At the end of each MC's timeline you tell it to go to play the next frame on the main Timeline.
If you want to export this to video you will have to choose the 'Time' option in export video dialog and input the calculated duration of your entire project.
Personally, I would use this convoluted method only if I absolutely have to, because of some project specifics.
Nick - Character Designer and Animator, Flash user since 1998 Member of the Flanimate Powertools Team - extensions for character animation