Draft2Digital publishing to library apps?

Since KDP recently update their terms and conditions to allow ebooks published through them to also be made available to library apps, I have uploaded my employer’s indie published books (on his behalf) to Draft2Digital. We finally got everything set up and selected only the Library option, but here’s my question. In your experience, how long does it take for your books to actually show up in Hoopla? The status on Draft2Digital still says “publishing.” How does it work, exactly? Is the book going to automatically show up in Hoopla if I search for it, or does each library have to specifically go looking for it in order to include it on their virtual shelves if enough people request it? Thanks! It’s all a little confusing.