Bob,

Your work to date has delivered solid data for owners of the classic (US) Prius (NHW11). They should follow your Type T renewal suggestions at 15k mile intervals.

I'm currently at 71k miles on my NHW20 (10k on the new Type WS ATF since the refill at 61k miles). My plan is to do an extra ATF refresh at 90K miles to give you one more sample point. My ETA to 90k is about 10 months so be patient.

JeffD