Google Search’s local pack has for a long time let you filter the local results by hours of operation. But I am not sure when Google added by the day of the week. I am not sure if this is new but I don’t think I’ve seen it before.
Shameem Adhikarath spotted this and posted about it on Twitter and I can replicate it, here is a screenshot (click to enlarge) where the hours filter shows the days of the week:
So if you filter this by businesses open on Saturday, RustyBrick will disappear. Google will take you into the Google Maps results for these filtered results. The query will not be refined within Google Search’s local three pack but rather you are taken into Google Maps with that filter.
Forum discussion at Twitter.