isupplier portal- GBPA price change request

Has anyone had complaints on the supplier change request process in regards to blanket agreement lines?  There does not appear to be a way on the isupplier user end, other than scrolling down the page, to find and submit a price change request for an item on a blanket agreement.  This can be very cumbersome for agreements with 100+ lines.  Any suggestions?  We have started allowing suppliers to use the comments section if it takes too long to locate the line, but then the buyer has to make the update which eliminates part of the automation/ease of using the portal.