This array formula should trim off any amount of letters before the first number:
=MID(A2,MIN(IF(ISNUMBER(FIND({1,2,3,4,5,6,7,8,9,0},A2)),FIND({1,2,3,4,5,6,7,8,9,0},A2))),999)
If no number is found, formula will give #VALUE! error.
Remember that array formulas need to be confirmed using Ctrl+Shift+Enter.