Biblical scholars agree that Christ wasn’t born and didn’t die in 1 AD, so that’s the “official” reason for the whole BCE/CE thing.
But, we all know that the real reason is anti-Christianity. If they could, they’d switch us over to the muslim calendar (if there is such a thing—and I don’t care enough to Google it).
I asked a BCE/CE advocate what happened in 1 CE to force the change in calendars. Like most liberals, he didn’t know why he supports something. He just knows that the talking head on the TV box told him to!
Since they are talking about a synagogue from the early Roman period, why not use Roman dates? "A.U.C. 700 to 900" (counting from the founding of Rome in 753 B.C.). Or use Olympiads and get everyone totally confused.