Actually, it's not all that new. For many years, it was Dollard Road from AR 282 near Mountainburg to the wilds of Crawford County. When AR 540 (I-540's predecessor) was built from Alma to Mountainburg in the 1990's, it became an extension of 540 back to US 71 (partially co-signed with an new alignment of AR 282, bypassing the old Silver Bridge over Frog Bayou).
After AR 540 became I-540, the half mile section of road became an East-West alignment of AR 282 while the rest continued to be posted as North-South.
However, the most recent change has redesignated this as 282S, though it is only posted westbound (eastbound is posted as TO 282)
Confusing? You bet! But, that's Arkansas: always "improving" things that don't need improving.