It is believed that HB stars and their progeny are responsible for the increase in UV flux found in elliptical galaxies, a phenomenon known as the UV upturn. These stars undergo different evolutionary paths depending on their temperature, with the redder stars evolving as bright P-AGB stars, possibly forming planetary nebulae, before eventually descending the white dwarf cooling curve. We exploit a theoretical model of stellar populations incorporating a hot P-AGB component with a fuel calibrated UV upturn and a system of UV absorption line indices to investigate the redshift at the onset of the UV upturn in massive galaxies. We analyse a large sample of massive galaxy spectra taken from the Sloan Digital Sky Survey (SDSS) -III / Baryon Oscillator Spectroscopic Survey (BOSS). We find up to 47% of our working sample to contain a contribution from old UV bright stars with the majority of old populations contributing up to 30% of the galaxy’s stellar mass.