U perm (14)
  r2 D2 U r2 U' r2 U' r2 U' r2 D2 U r2 D'

2 edge flip (UF/UL) (16)
  r U2 r' D2 r2 U r' U r' U' r2 U' r2 D2 r U r' U

4 edge flip (U edges) (20)
  r D r D r2 U r U r D2 r' U' r' U' r2 D' r' D' r' U2

R (23)
  U2 r2 U r2 U2 r D2 U2 r' U2 r2 D' r2 U2 r D2 U2 r' U2 r2 U' r2 U2

10 edge flip - at least 29


God's algorithm table for edges: Depth New Total 0 1 1 1 9 10 2 45 55 3 216 271 4 1053 1324 5 5103 6427 6 24515 30942 7 114278 145220 8 523750 668970 9 2349548 3018518 10 10231366 13249884 11 42562570 55812454 12 162294456 218106910 13 500023810 718130720 14 835157223 1553287943 15 300304986 1853592929 16 4351249 1857944178 17 1409 1857945587 18 12 1857945599 19 1 1857945600 20 0 1857945600 The depth 19 position is 10 edge flip with UF/UB, RF/RB, DF/DB swapped.