There is this parallel too to consider, 2 * 31 = 62 days later:

Ab1-1	Ab1-2	Ab1-3	Ab1-4	Ab1-5 (675)	Ab1-6	Ab1-7
Ab1-63	Ab1-64	Ab1-65	Ab1-66	Ab1-67 (737)	Ab1-68	Ab1-69