Not the prettiest script but..
Code:
raw 473:*:{
  .echo -q $regex(next,$2,(\d+)$) 
  join $iif($left($2,- $+ $len($regml(next,1))),$ifmatch,$2) $+ $calc($regml(next,1) + 1)
}
raw 474:*:{
  .echo -q $regex(next,$2,(\d+)$) 
  join $iif($left($2,- $+ $len($regml(next,1))),$ifmatch,$2) $+ $calc($regml(next,1) + 1)
}
raw 475:*:{
  .echo -q $regex(next,$2,(\d+)$) 
  join $iif($left($2,- $+ $len($regml(next,1))),$ifmatch,$2) $+ $calc($regml(next,1) + 1)
}


Edit: It seems to bugger up on channels with numbers in (perhaps not surpisingly). Ill try to fix..
Edit2: Think I fixed it.