HY270 vs HY70 in top of grouted cmu

There is a direct substitution letter for HY270 to replace HY70 which indicates the values of anchors in the face of cmu are higher for HY270. However, it appears the values for anchors in the top of grout filled cmu are considerably lower for HY270 vs HY70. The 2014 catalog I have indicates an allowable tension bond for 5/8" anchor 5 5/8" embed of 1165 lbs for HY70. For HY270 it indicates an ultimate tension bond of only 1090 lbs. Have the values reduced that significantly and/or is it still a straight substitution?