Had a project recently that was effectively “Hey other teams, you have until $date to make this change or you will lose $feature”

The deadline was extended by a month, and we still quietly didn’t make the breaking change on our end for another month after. Every team impacted (until they made the change needed) got emails weekly about it, even into the “quiet” extended deadline. Emails went to whole teams so it couldn’t be lost by one person going on vacation or something.

Day after breaking change (more than three months after first contact) I sent out the final email to any teams that still hadn’t done the needful. “Hey, looks like your shit was still wrong when we did the thing we warned about. It’s broken now.”

Over a week after breaking change, ten minutes before I’m off for the weekend: “Hey, we’ve been troubleshooting for a while trying to figure out why $feature no longer works. This is business critical for $reasons. How can we get this resolved?”

“Please see the attached email from over three months ago (attached).”