Please do not worry!

Your favourite characters are in the settlement, just busy doing other things at the Travelers stopping place. 

Edward

As you already know, Edward is a very responsive person, so he volunteered to help twice.

And so he disappears while you are completing the "Travelers Stopping Place" quest on stage 5 and come back on stage 11 and one more time he will go on stage 29 and come back on stage 30.

Luna

Luna, as a reliable friend, will also help with this quest, and therefore will not be available from stage 34 to 37.

Halvard

Our old friend Halvard will fall into a trap, so you'll need to get him out as soon as possible, so complete stages 18 to 21 to help Halvard return to the settlement unharmed.
With love,
Your Farland Team!