Query against existing redirects upon url creation

Would it be possible to include a query against existing page redirects when creating urls of pages.
We have a client who hosts job listings on their website through a webapp and upon creation a URL is assigned for that listing but once the vacancy has expired it is removed and replaced with a redirect so it does not 404.
We've recently encountered an issue in that a listing was created and the name happened to match an existing redirect causing the vacancy to be inaccessible which made me think maybe a query against redirects would ensure this no longer happens.