I’ve always been partial for Friday night through Friday night.

You start off over the weekend, when you have energy and can survive the two days alone. Ideally no Friday releases so the transition is calm, but as the writer says the batches might fail.

You spend the week fixing whatever breaks. You’re cleanly off the Monday to Monday sprint, just doing on-call/ops.

You finish Friday evening and immediately get Friday night and the weekend to recover when you need it most.

This post was discussed somewhere else and I saw someone say that their work does Firday noon to Friday noon and their work gives the outgoing on call the rest of Friday off. I feel like that's even better because 1) it recognizes the hard work that the outgoing on call put in 2) it give the incoming on call a few hours to get up to speed while they still have the support of the other engineers on the team.

Maybe I'm taking you too literally, but I wouldn't want to have a handoff sync-up (or any meeting, really) on a Friday night, nor push that earlier so significant things can happen between sync-up and the actual shift in responsibility from person to person. Friday-to-Friday does sound good.

One thing I really liked in a previous job was a split daytime-vs-nighttime rotation. It was well worth a little annoyance to set up in our tools. One week you'd be the 'daytime' oncall for business hours (something like 9-5 Mon-Fri, though we might have tweaked those hours a bit; it might have been 10-6 or something). The next you'd be on call for the complementary time (5-9, weekends). You were on call for the same total amount of time, just smeared over two different weeks. It ended up being less of a burden to optimize your schedule for a reasonable response time, but operational work still got done. And in practice awareness of operational issues was not too hard to maintain between the two members of the split.

(I think the best thing, if you can swing it, is probably a follow-the-sun rotation where there are three teams distributed 8 hours apart around the globe, and they trade off 8-hour workday shifts. But a lot of uncommon things probably have to be true of your organization for that idea to even be on the radar.)

That was exactly my reasoning too when I set up our on call roster as Friday to Friday, though for us Saturday is the busiest day in terms of customer activity, so it was a no-brainer.