Aeroplan has told us that there is no travel advisory for Bangkok (at least as far as AC and they are concerned) and accordingly won't change our flight free of charge. As we are only there for 2 nights (and on a budget) we'll be chancing it from the 25 - 27. Hopefully the situation only gets better, rather than worse.

Every map that I can find, shows the Kho San Road area as a low risk flood area, however it seems that media reports are somewhat slow to update anything.