Does anyone (this probably means Sandy ;-)) know how long Pyrocat-HD lasts after mixing?

I do all my film developing in Jobo expert drums and I'm wondering if it'll last long enough for me to mix up a big batch, develop, stop, fix, rinse one set of negatives, rince and dry the drum and then repeat on another set. If it will, how many sets can I reasonably get through? With the small quantities of sols. A & B involved (even at 2:2:100) it seems it would be easier to accurately mix up a batch that is a litre or two in size than to mix a few that are each 200-500ml.

Thanks,
Dean