I implemented the following change as suggested in ATR-29889:
(MBTS_A[x2] | MBTS_C[x2] | MBTS_A[x1]) & (MBTS_A[x2] | MBTS_C[x2] | MBTS_C[x1]) to ( MBTS_C[x2] | MBTS_A[x1]) & (MBTS_A[x2] | MBTS_C[x1])
tagging: @tamartin @aikoulou @khoo