That's not following vpd in flower. Those temps will push the plant into taking up more water>nutrients. The plants are undoubtedly, completely undoubtedly happier when RH is closer to 70% for most of flower at higher temps, be it hps or led. I am kicking myself for not doing this sooner. You use less nutrients over all, less electric, less work, happier plants, bigger plants, more yield and no mold (environment depending).
With hps the lights need to be moved further back than normal, this allows the ambient temps > humidity to be higher without the bulbs scorching the plants. You will lose some intensity, but that is completely ought weighed by how happy the plants become. For years people have used poly-tunnels in gardens, you can't even see through most of them, yet on the inside are tropical plants, veg of all sorts, all green as fk. The heat and humidity as a catalyst to high yield has been overlooked by us ''growers'' for a long time. Our focus of yield reward has been entirely on ''light W'' and ''nutrients''. Essentially, low humidity is a detrimental mistake (one I also made for a long time).