It's a very nice looking skirt and I imagine the designer took the blocking into account when choosing the yarn. The alpaca should block out and pretty much stay blocked. However, the acrylic will block as well with steam only- NO IRONING (ironing will either melt the acrylic or make it super soft and limp) or by soaking, towel drying and possibly pinning into shape, then letting air dry. It might have to be reblocked to remain crisp each time but overall, the ribbing will keep the pleat.
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