No, sorry the breakpoints are hard coded in the interests of performance (there are a huge number of things that use them).
I would however go with @habitualshaker’s solution and just change the background size a bit to keep it off the text while leaving the text left aligned until the actual breakpoint when you centre it.
You could of course use the vis child to control for both size and aspect ratio combined to show / hide your alternate backgrounds but position them using the adv position child rather than using the built in background/overlay. This seems a bit convoluted though.
Might just do what I did for the home page: Two versions, one for bigger screens, one for smaller. Means a bit more code on the page (unless I use Agent) but in the real world, it’s not a biggie.
Cheers.
BTW: Missed an opportunity: “Sorry, that is not a feature of this stack”.