Delays on order - no communication until pushed

I have ordered before and been very happy so recommended your site to my mom. We placed and order for 3 books on the 22nd March with an ETA as per the site of 5 - 10 working days......15 working days later we are still waiting on the books and only after sending 2 mails requesting an update have I been informed the 1 book is not available and is on backorder however it will not affect the processing of the other 2 books orders........then why are the books not here yet? We need the books by Tuesday which would have been almost 20 days after the order was placed. Will Loot get the books to us before then???