There’s been a lot of speculation about this question on multiple threads.
With the exception of individual titles that were on Pre-Pub, the exact Pre-Pub products that were canceled will never come back.
However, the books that made up those products may, at some point, come back in a different product offering.
In this process, our goal is to optimize Pre-Pub and push products through more quickly. To achieve that goal we reduced the number of Pre-Pub product offerings. Once optimized, products will move through the system more quickly and, in turn, new products will be added. So it is possible that this will involve some of the books from the recently canceled Pre-Pubs returning.