Hi Greg, I think this is great on its own, but it has been previously established that Lawanda's sister Lena is the Colony Director, and that Lawanda is Lena's secretary. So, I'm not sure how this works with that ... do Lena and Lawanda both join the colony together in Signpost 1 and then Lena works her way up to Director quickly?
Or wait, is a lot of what you wrote just backstory (happened sometime before the story starts) that explains why she's masquerading as fertile? If so, I can see how that works ... newcomers aren't generally allowed to join the colony unless they're fertile (thanks to the influence of the fertiles) ... and if it was far enough in the past it would give Lena time to become Director.
Or maybe (I like this a lot better), Lena and Lawanda were not together during the apocalypse, and Lawanda only found the colony after searching for Lena? This is kinda cool ... I can picture a scene with Lena telling Lawanda, "look, I know you're my sister but even though I'm Director I can't make an exception for you ... you better you hope you test as fertile or I'll have to send you packing..."