I would have thought summer vacation would effect weekdays more than weekends. We could put it down to the warm weather we had 2 weeks ago compared to the miserable weather last weekend, that likely softened the drops. Kids on vacation are mostly under 15 also
Even still, CBM's performances in general tend to closely allign with the UK. The GBP gross is usually around 10% of the domestic dollar gross. With that in mind, TSS seems to be over performing in the UK compared to the US, more than any CBM in recent memory. Being free to watch could be that reason.
JC and BW aren't great to compare with because they aren't actually free, you still have to pay around £20 here to watch them on D+