It shouldn't be surprising if you understand sale patterns and consumerism.
Of the 4 holidays you listed, 3 of them are "Hallmark" holidays with holiday specific products (cards, candy, etc.). All 3 of those holidays fell on the 2nd week of the 2-week flyer, so the time from the holiday to the end of the 2nd week equals to just a few days. This is important because the holiday specific products can then go on clearance, making room for the next "Hallmark" holiday.
Valentine's Day is a "Hallmark" holiday and falls on the 1st week so it's a 1-week flyer. You can't have Valentine's day sales on Week 1 and repeat those sales for Week 2 when the holiday is over. They need to start moving product for the next "HM" holiday, Easter.
It shouldn't be surprising if you understand sale patterns and consumerism.
Of the 4 holidays you listed, 3 of them are "Hallmark" holidays with holiday specific products (cards, candy, etc.). All 3 of those holidays fell on the 2nd week of the 2-week flyer, so the time from the holiday to the end of the 2nd week equals to just a few days. This is important because the holiday specific products can then go on clearance, making room for the next "Hallmark" holiday.
Valentine's Day is a "Hallmark" holiday and falls on the 1st week so it's a 1-week flyer. You can't have Valentine's day sales on Week 1 and repeat those sales for Week 2 when the holiday is over. They need to start moving product for the next "HM" holiday, Easter.