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There's no "early qualification" for P25K status, so you'd only receive benefits next year.
However, there is early qualification for E35K status (assuming you qualify before ~Oct.).
The Altitude bonus miles benefit is based on the calendar (an odd exception to the usual status year), so if you choose the 35% bonus miles upon qualifying for E35K status (let's say in a month), you'll (retroactively) receive a 35% bonus for all flights taken in 2017.