I'm just a pleb and this is my first cycle, but I'm going to use the paper I produce for the Michaelmas term of my MSt. I had a lot of things weighing down on me that kept me from working on my writing sample last semester, and I just think it's a bad idea to try to resurrect it. I think the general answer here is, though, that it doesn't matter one bit, as long as it's significantly better than your first sample and you've gone through 10+ drafts of it read by professors with some standing and experience in the discipline (or at the very least the best professors available to you). My problems this cycle were: lack of pedigree, poor sample, and bad fit. The first thing is out of my (and your(?)) control. I had no idea going into college that going to a small liberal arts college that, while prestigious, didn't have a ranked PhD program, would hurt me SIGNIFICANTLY. The other two things, however, are in my control, and hence the things I'll work on. I'd probably encourage you to do the same. Write up a brilliant sample and put in the extra hours to explain in your SoP why you're a good fit for the program (and do try to make your sample subject be your AOI).