I'm still not clear on Base layers and sleep clothes. I'm looking at a mid to late March AT thru-hike NOBO start date. Normally on any typical spring and fall backpack trip I would have the following hiking clothes: short sleeve poly top, boxer briefs, convertible pants, Darn Tough crews, trail runners, dirty girl gators and brimmed hat. I have an Arc'teryx long sleeve zip neck polartec fleece pullover (not sure if it is considered light weight or medium weight) that I wear while hiking when the short sleeve shirt is too cold by itself. I have a Ghost whisperer down jacket for camp and Outdoor Research helium II rain shell and helium rain pants for rainy weather and wind shell. I have a buff that I wear with my hat when cold and a beanie that I wear at night when cold. I have glove liners, possum down gloves and rain shell mitts. I typically don't pack sleep clothes other than a pair of down socks. I do carry an extra pair of boxer briefs and darn tough socks. I know that there may be days and nights colder than what I typically backpack in, but I'm not clear on what I will need. I have a Smartwool Merino 150 long sleeve top and Patagonia capilene 3 long bottoms that I am planning on taking. Is it likely that I will want to hike or sleep in them. Will I want to bring two pair, one for hiking and one for sleeping? If I bring two long sleeve Smartwool 150 tops, will I still need the short sleeve poly t-shirt. Will I need something extra for laundry day?