While it is the job of a GM to ensure that our players always have something to do, there are times when we will run into a writers block and be unable to write. This happens more often than some people realize, and when it does, our players can suffer. However, there are times when we as GM's do not think it is prudent to make a GM post every day unless it involves the usage of an NPC character to do the talking or to move events along in a fast paced fashion (Although we prefer not to do this, as it'll leave other players behind)
In any case, I've made it rather clear multiple times in the past that my private message box is always open and that if anyone has idea's or if they are concerned that their characters are being left behind, to always PM me. There is a chance that - like what happened with our pilots - part of my GM post will disappear and leave them with nothing to do, other times I may end up forgetting that we have players stuck.