My contract has been extended by another two weeks for the time being. HR asked me if I wanted to apply for a permanent job (I think they are pretty sick of temps by now, judging by the problems that have gone before) but I told them it didn't suit my circumstances (as a burgeoning writer and all that) however I could stay on until December or January. It doesn't sound like they'll keep extending my contract by more than two weeks at a time, probably because I'm replacing someone on the long-term sick who might come back at any time.
This is all good. I'm feeling quite Buddhist about the whole situation - if I stay on until December or longer, great; if not it means I can start editing sooner, which is also great. Whatever happens I'll have a least one months' wages in the bank so I won't starve.
Realised yesterday that the next weekend is a long one, W00t!