Events have certain days they come out on. For example, UC always starts on Wednesday so the final two days are Saturday and Sunday. Here what we had was Mythic Colosseum starting on Friday. One of the fun aspects about MC is we get to see a new mythic slightly before it gets released. Hence, the SCB was delayed to Monday, a few days afterwards. The SCB is lasting 11 days so that it aligns with the usual Friday - Friday routine. We had a very similar thing happen last time a monster was showcased in MC (Rodeknight).
So ultimately we got one less SCB than normal. However, there’s a reason for it so I don’t think anyone should panic or make a complaint about 4 gems we didn’t get. I mean hey, we literally got 10 gems for free today in our inbox as a Easter celebration from the Devs!
I think the issue here is that the Devs should schedule Mythic Colosseum to start on Wednesdays. That way they can release the new mythic on a Friday and not disrupt the SCB schedule.