If you are using PBASIC 2.5, then try using the select / case statements like so:
select (timer)
case 0 to 300
'code to make robot go straight
case 301 to 500
'turning code
'.....etc
endselect
that way it will go to the section of code you want, and it stays neat, orderly, and you dont have to mess with a ton and a half of labels
