mattwnz: Thanks for that. That then shows that they were aware of this problem last month. That is certainly not good that they haven't fixed their systems.
I def. got the impression that the system "ban" on over-riding the price was purposeful and aimed at this one product; they clearly indicated that it wasn't something they'd faced before, so it must be that head office has decided to stop it being sold below $299 outside of specific sale times (which of course doesn't help when they're obliged to match their sister store's lower price!).