Scenario: A popular restaurant chain allows you to search for availability and accepts reservations via its website. It can be nearly impossible to get a reservation unless you just happen to check at exactly the time when someone else cancels. The software I'm looking for allows you to provide info about the location, date, and a time you want then it notifies you by email/text when something opens. You can search for several locations and dates at once. You still have to jump in fast to snag the spot, but knowing a spot has opened gives you a fighting chance. More importantly, you aren't wasting time checking for space multiple times a day; the whole process is automated.
It was suggested to me that maybe this is "sniping" software, but all the snipers I see are specifically geared to auctions (usually eBay). Maybe what I need is a form of sniping software, but I can't find it. There are several online sites which provide the service I'm looking for, but I don't want to pay them per search since I have an ongoing need and it would get quite costly.
Any ideas? Search terms to use maybe?

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