Is there a way to upload from a spreadsheet into iProcurement for releases?

 We have a situation where there are 1,000s of releases that need entered against Blanket POs at any given time.  Is there a way to upload to iProcurement all these requisition lines that would then go through approval workflow and flow into Purchasing to automatically create the release?  Entering these into iProcurement manually and then splitting the lines, (since they all have to go to different coding, i.e. markets), is too time consuming of a solution.