The ONCY report offers Phase III H&N response results from a metadata snapshot of the metastatic disease group. This double blinded (but fully enrolled) randomized Trial remains blinded. Without singling out the named metastatic group it typically takes 8 weeks to get a meaningful spread in data for these H&N patients (learned from 2 Phase II trials), but I suspect that the this 6 week data (the choice at this point was 6 vs 12 week) was made to minimize a statistical hit, and was done now because a late July PFS snapshot before enrollment had completed suggested that the metastatic results could show an earlier spread.
Today's results might lead to an earlier unblinding than was previously expected.