I have the SBL edition as part of my logos package but apparently need to upgrade in order to be able to purchase the SBL verse diagrams. It says it is "not available." However, I can purchase the NA28 diagrams, even though I don't own the NA28 in Logos. Doesn't really make sense does it? If I want to be able to make full use of either of these diagram packages I either have to spend $300 to upgrade or purchase the NA28 for $100 and then spend another $50 for the diagrams. Logos, please consider making the SBL diagrams available for those of us who already have the SBL edition (and currently use it in their seminary studies.) I am ready to spend my money to purchase the SBL diagrams whenever you are ready to sell them to me.