What would happen if in a VVAR table for CFF2, both TSB and VORG data exist & they conflict?

Belleve Invis
Belleve Invis Posts: 269
edited November 2017 in Font Technology
Since the y-maximum may not representable in value + delta mechanism (the point being top-most changes), TSB and VORG data may run into a conflict about the vertical origin of certain glyphs. In this situation, what would happen for rasterizers? How did they decide vertical origin?
(for TTF-GVAR, the spec said that phantom points are always prioritized.)