The Green Line's Signals Broke at Kenmore Friday Morning. The Signal Shutdown Starts Saturday. Who Scheduled This, a Screenwriter?

Friday at 7:01 a.m., the MBTA reported signal problems at Kenmore that delayed Green Line trains. By 8:43 a.m., service was back to normal. Universal Hub noticed the obvious: this was the day before the T shuts the Green Line for, yes, signal upgrades.

Saturday and Sunday there are no trains between North Station and Babcock Street on the B, Kenmore on the C and D, and Heath Street on the E. Shuttles cover Copley and Back Bay, and the Orange Line is free between Back Bay and North Station, NBC Boston reported. Budget up to 25 extra minutes.

It's Halloween, of course, with more than 100 Boston streets permitted to close for trick-or-treating and block parties. So the kids are walking anyway.

To be fair, a signal failure the day before signal work is less irony than evidence. It's the argument for the shutdown, delivered live.

What we still don't know: how many more weekend closures the signal project needs, and when riders will stop seeing Kenmore in the alerts.