I have received today the hard copy sheet that Fuji UK offered in Choose Film. The spectral sensitivity curves are identical to the old Velvia. My old Velvia technical data sheet reference number is AF3-960E, and as far as I know is the latest sheet published in Fujifilm global, maybe there was an older one with differente spectral sensitivity curves. BTW, the spectral sensitivy you mention is more likely to be for Velvia 100 and Velvia 100F.
In fact, the only differences I have detected are the sheet film base, the old Velvia used 205 microns cellulose triacetate, the new Velvia 50 uses 175 microns polyester.
And the relative humidity recommended for medium term storage, in the old velvia 30-60% was recommended, in the new Velvia 50 30-50%.
Everything else is identical.