Improvement for settlers rescues

Just now I logged on and went to rescue my shippers and then my Atlas runners who got themselves caught. Sadly as soon as I entered my Atlas Runners zone I click on the portal and left it. I found myself unable to go back inside that zone and the rescue/ransom options were grayed out.

I lost all my 6 Rank5 Atlas runners due to this small mistake.

I think the portal should be removed until the boss dies or a warning should pop just like In many zones with consequences such as the Labyrinth.

I am sad for the loss of my atlas runners ;(