A7iii - "grab shot" settings for weddings

[MalthouseMark]

Hi, I'm a new convert to Sony A7iii from Canon 5Diii. Literally only 8 days into the ride so far. I'm diving straight in to the Sony community to say "hello" and ask a question.

I've been doing a LOT of reading and watching YouTube videos in an attempt to get the best out of my new cameras. Having been playing with them I'm fairly confident of my choices for various settings.

The final bit of my jigsaw is to set up user modes on both bodies. One of those will be a mode for flash use with Godox flashes. I'm fairly happy with this - things like turning off silent shoot and electronic first shutter plus making my shooting system familiar to what I used to do on the Canon.

One bit I'm less sure about though, and the reason for this question, is "grab shot" images. On the 5Diii I had one button I'd press that put it into continuous focus and I'd hope to be in the ball-park for exposure. On the A7iii I'm using AFC for focus anyway. I've put in both back button focus on AF-On button and eye focus on AEL button. So I'm mostly there already - but exposure... I'm often a "manual only" sort of guy but watching one video about using Auto-ISO with 1/250th minimum and Aperture Priority has made me think about this for some sections of the wedding.

And the other aspect of this is I tried full Auto mode point-and-shoot as my wife came in the door. And it nailed it!

This has made me question what people do for those wedding grab shots. The images you see out of the corner of your eye and point and hope! It could be a bridesmaid running towards you or the mother of the bride falling over the cake. Who knows.

I figured as I'm new to the camera and to Sony I might as well join in the community and ask.

So how do you have your camera set so that one minute you're shooting in (say) manual at ISO 100 and 1/50th on f/2.8 and the next you really need eye detect, 1/2000th and ISO 6400? (Or whatever settings you think are appropriate.)

Do you just turn to Auto? Or do you have another "Cunning Plan" (reference for fellow UK readers).

Thanks,
 Mark