What ischillstep?
On the downtempo line between asian underground and psychill. Grew out of dubstep (uk garage line).
EMERGED 2011
CHILLSTEP
Slowed-down dubstep that borrows the pads and calm of ambient and chillout, linked to the UK in the late 2000s.[1] Blackmill, SizzleBird and MitiS are named as early names, with Phaeleh and Faodail pointed to as the more ambient end.[1][2] The name turns up around 2011 and the style peaked about 2012 to 2013, when YouTube was where people found it.[2]