CTD asc filenames have typically been 'd or u' YYMMPPP.asc & .hdr (d or u = down or up casts; YY is year; MM month; PPP order occupied or proc #). To standardize the file naming, the .asc & .hdr have been renamed to match the bottle-corrected csvs, YYYYMM_LLLLSSSS_PPPud.*, where YYMM is year month; LLLLSSSS is decimal Line & Sta (minus the '.'); PPP is order occupied (or processing number); u for upcast, d for downcast.