Hi
If you blasted 15k urls and didn't see a single backlink with the link checker, then you should just keep on scraping new lists and blast them.
As a experience I find that most of the lists what are shared for free are mostly non AA lists (people think that if it's successfully posted then it's AA). When you are just starting your sb journey then just blast the hell out of your lists and run them through link checker.
Just when you find the aa link, then try to expand links from that domain. Scrape the auto approved url to the root and scrape all pages of this site (if one page of this domain was auto approve, then more than likeley other pages of this site are aswell)
If you blasted 15k urls and didn't see a single backlink with the link checker, then you should just keep on scraping new lists and blast them.
As a experience I find that most of the lists what are shared for free are mostly non AA lists (people think that if it's successfully posted then it's AA). When you are just starting your sb journey then just blast the hell out of your lists and run them through link checker.
Just when you find the aa link, then try to expand links from that domain. Scrape the auto approved url to the root and scrape all pages of this site (if one page of this domain was auto approve, then more than likeley other pages of this site are aswell)