Hello! Just received this from a GC I was reluctantly obliged to work through at the beginning of the year. I have never been paid by a GC before. I don't know what they want... All previous invoices to them for this project have been simply my invoice, which got paid. What is the retainage? Who does this benefit? "Please send in a pay app with release of lien for your total contract amount and approved changes – less 2.5% retainage." Thanks in advance, Grahame Menage LLC