Colonists unavailable from dropship [0.58 - Windows 7 x64]

[shockedder]

Build 0.58.
OS Win 7 64 bit Ultimate.
Problem: Other/Balance Issue

After calling several drop-pods with colonists, the call colonist drop-pod (capsule) is greyed out and cannot be triggered.
Since there is a high attrition rate in colonist population due to various issues, this makes the situation untenable in the base.
if this is a hard limit I suggest it be removed, otherwise it should be fixed (please).

[shockedder]

This cleared itself after a while (and a few reloads), but now I'm in the same spot after a couple of colonists died again.
Any information ?