"In other words, Honda is driving business to their dealerships with their nanny maintenance system that tries to get you to do more maintenance than the car actually is asking for. This is possibly the biggest thing I dislike about the Clarity (the other is that the electric motor isn't big enough to propel the car in all situations by itself).[/QUOTE]"
Which is why I pay zero attention to the Honda Maintenance Minder. May be useful to some folks I guess but useless to anyone with a modicum of common sense.
Love the Clarity the car...Honda USA however is pathetic and their dealership network follows suit.
To answer the OP question...in my opinion any OCI should be based on ICE miles. Currently I use 15,000 miles on the odo as the barometer because at 15k odo...I have ~4500k miles on ICE which equates to using the ICE 30% of the time. At one year since OC, I will draw a sample of the oil and send for analysis to gauge life left and will base next OC on scientific data.
After 2 oil changes...and two lab analysis...I will probably settle on 20,000 miles odo/2 year OCI. This assumes the lab results will fully support oil life out to 24 months...which I fully expect.
Keep in mind 20,000 miles on odo only equates to 6,000 miles on ICE if I maintain the 70% EV/30% ICE usage split which I most likely will...or I'll adjust accordingly.
Hope this helps.