When Do You Change Your DI Resin?

[lastlight]

I find my colour-changing resin isn't entirely changed once the tds meter starts reading 1. There are pockets of 'new' coloured resin still... I give the canister a bit of a shake and this gets me usually a few more hours of zero tds but then I replace the resin. I would trust a meter more than the resin's colour if possible.