No need for a timer.
The on OP and on DEOP events trigger when a user on a channel is opped or deopped.
Format: on <level>:OP:<#[,#]>:<commands>
Example: on 1:OP:#mirc,#irchelp:/msg $opnick Please do not abuse your Op status
Generally the op event happens immediately after the join.
There is no need for a space between the colon and the left bracket...
Works just fine.