The new estimates are now expected in the March quarter next year rather than the current December reporting period, with an updated life-of-mine production profile to also be reported.
The latest drill results have included 6m grading 20.5 grams per tonne gold from 1211m downhole, within which 0.5m at 167gpt gold was recorded.
The hit was made at a depth below surface of more than 900m, and more than 400m below current reserves.
Two more holes are currently in progress.
Reserves at M1 South grading 10.2gpt and extending to 500m below surface were last estimated at 650,000 ounces.
WAF has previously stated it's targeting a 4-5 year extension to the 6.5 years current underground reserves support.