YES(?,O(n^1))

Problem:
 b(a(a(b(a(b(x1)))))) -> a(b(a(a(b(b(a(x1)))))))

Proof:
 Bounds Processor:
  bound: 2
  enrichment: match
  automaton:
   final states: {3}
   transitions:
    a1(20) -> 21*
    a1(15) -> 16*
    a1(12) -> 13*
    a1(16) -> 17*
    a1(18) -> 19*
    b1(17) -> 18*
    b1(14) -> 15*
    b1(13) -> 14*
    a2(30) -> 31*
    a2(32) -> 33*
    a2(29) -> 30*
    a2(26) -> 27*
    b0(3) -> 3*
    b2(27) -> 28*
    b2(31) -> 32*
    b2(28) -> 29*
    a0(3) -> 3*
    3 -> 12*
    17 -> 26,20
    19 -> 14,3
    21 -> 13*
    33 -> 18*
  problem:
   
  Qed