Looks like Google Merchant Center Feeder will need to be update because of change to "availability" attribute in this announcement from Google for changes going into effect on 9/30/14.

https://support.google.com/merchants.../3097504?hl=en

"We are simplifying the ‘availability’ attribute by merging ‘in stock’ with ‘available for order’ and removing ‘available for order’. All items that can be shipped in a timely manner can now simply use the ‘in stock’ value. In addition, we are now offering an ‘availability date’ attribute that you can use to let shoppers know when pre-ordered products will be available for delivery."