Most likely, at the end of each Episode will be an "ending" of sorts that would take you back to the main menu. This *could* be an updated end credits scene though I can't confirm that at this time.
But let's pretend that it would be an end credits scene, this scene would require a script to activate. Let's say this script is called "end_ep1" for example... in Episode 1's release this script activates the ending whereas when the Episode 2 update is released we'll replace the "end_ep1" script with a warp script to go to Nar Shaddaa but it this new warp script is still named "end_ep1" to make it compatible with Save Games.
Though our primary goal is finishing the actual Episode off first, so take all this with a grain of salt as things can change with time.