Here is an availability chart:
Available Now – the title is in stock
High Availability – greater than 75%
Medium Availability – 50% to 74%
Low Availability – 25% to 49%
Very Low Availability – Less than 25% (mostly rare or no longer manufactured titles)
So, you will get those games when they are available. If you really want them, keep them at the top spots in your Game Q. Gamefly usually ships games out of your top five games on your Game Q.