Final tally was 35 hours.
To recap, broke a piston last year with 2100 hours on the motor, no clear cause. Decided on new Yamaha powerhead versus a rebuild thinking it would be better for reliability and longevity. The new factory powerhead always burned some oil but with 250 hours started burning about a quart every 2-3 hours. Yamaha suggested their "deep engine cleaning" which cost about $800. No help. Tore the powerhead down and found glazed cylinders. Honed the cylinders and rplaced rings. All told about $8k for the new powerhead last year and $7k for the deep clean and rebuild this year.
As for the cause, everyone's run for cover. Yamaha/Dealer said it was maybe bad gas, bad break in, too much trolling, too much high speed running, blah, blah, blah.
Anyway, the boat is back in Sarasota for the winter and the Kingfish are in.