YES

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

Proof:
 Bounds Processor:
  bound: 3
  enrichment: match
  automaton:
   final states: {1}
   transitions:
    a1(19) -> 20*
    a1(11) -> 12*
    a1(43) -> 44*
    a1(46) -> 47*
    a1(18) -> 19*
    a1(45) -> 46*
    a1(17) -> 18*
    a1(13) -> 14*
    a1(15) -> 16*
    a1(41) -> 42*
    a1(47) -> 48*
    a2(57) -> 58*
    a2(85) -> 86*
    a2(81) -> 82*
    a2(53) -> 54*
    a2(83) -> 84*
    a2(87) -> 88*
    a2(86) -> 87*
    a2(55) -> 56*
    a2(79) -> 80*
    a2(49) -> 50*
    a2(56) -> 57*
    a2(51) -> 52*
    b1(12) -> 13*
    b1(42) -> 43*
    b1(16) -> 17*
    b1(40) -> 41*
    b1(14) -> 15*
    b1(44) -> 45*
    f20() -> 2*
    b0(3) -> 4*
    b0(7) -> 8*
    b0(5) -> 6*
    a0(10) -> 1*
    a0(6) -> 7*
    a0(2) -> 3*
    a0(4) -> 5*
    a0(9) -> 10*
    a0(8) -> 9*
    b2(52) -> 53*
    b2(80) -> 81*
    b2(50) -> 51*
    b2(54) -> 55*
    b2(82) -> 83*
    b2(84) -> 85*
    b3(94) -> 95*
    b3(90) -> 91*
    b3(92) -> 93*
    a3(97) -> 98*
    a3(96) -> 97*
    a3(89) -> 90*
    a3(93) -> 94*
    a3(91) -> 92*
    a3(95) -> 96*
    17 -> 49*
    48 -> 15*
    46 -> 79*
    88 -> 51*
    58 -> 43*
    86 -> 89*
    1 -> 4,6
    20 -> 40,8
    9 -> 11*
    98 -> 55*
  problem:
   
  Qed