Yes that looks exactly like my problem. I have converted my groom to hair cards using the new hair card plugin, rendering them with TAA set to 5 in MRQ and that solves my problem by the looks of it. The TAA setting is needed because the hair is simulated like cloth and cloth can’t be rendered with overrides because it is evaluated on every sample not every frame. It may be worth trying it directly on the groom with these TAA settings.