Could have been an ATC directed 'turn right IMMEDIATELY!' followed by a TCAS. Had that exact scenario last month. Right turn resulted in approx. 1 mile lateral offset, RA directed climb resulted in traffic going 200' below us, Head on, FL180, 600 knot closure. Traffic climbing to above FL240 while we were descending to FL150.
Reminded me of a head on, offset BFM engagement.
NOTAM - ATC controller training in progress