I have 2 CY7C68013A-100AXC's. Both are Rev B with fab code of 04. The one with datecode 0537 has Lot# 645546. The other one with datecode 0931 has Lot# 627127. If both are from the same fab built almost 4 years apart, can the older IC have a larger Lot # than the nearly new IC? Can Lot #'s repeat?