Older Cal. 321 are listed at 35 hours power reserve. Cal. 861, 1861, 1863, 1866 are all 48 hours.
It's not uncommon for a freshly serviced watch to run a bit longer than the power reserve official numbers. It depends on the condition of the movement also.
The manual winding Speedmasters should be wound once a day.
Cheers, Al
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