About blanket purchase agreement (BPA) max line items limit

My customer asked that they are not able to enter more line items into a blanket purchase agreement (BPA). What can they do? Some people told them they hit max 1500 lines and need to create a new BPA and go from there. They further asked can they still use the old BPA number (that means to change the old to new and the new to old). What would be the best way to handle this situation?

Thanks in advance

milic