I think I may have heard this before, long long ago. Or just possibly something my father talked about as a local (Shropshire) usage of 'when' where you are getting 'until'. Too many dead brain cells ago for me to be sure.

I think this is related to other sentence constructions trying to get the same or a very similar message across.
- He was busy to the point that he didn't have time to eat.
- He got busier and busier until he didn't have time to eat.
You might want to check with Bel but I think it works in French as well:
- 'Il était pressé jusqu'au point où il n'avait pas le temps pour manger.'

And possibly Latin, but I know I can't remember enough of that even to try and construct the sentence!