I've a number of routes with similar fluctuations and low LFs despite having a CI of 90 and RI of 100, no or limited competition, and well spaced departures. I did have some problems with spacing of departures (using the gaps in the schedule of LH aircraft on SH routes is no longer a good idea, I've discovered), but once I fixed those, some of these problematic routes remain. I haven't yet been able to isolate what has changed or why these one aren't working like the rest. Unfortunately, I've also made a couple of poor long-term decisions lately and those and my just-getting-by on what I have, means I'm now in a downward spiral. I like the changes to 1.3 to make growth more challenging, but I'm puzzled by exactly why some otherwise sound routing decisions have proved so problematic.