sadly you have to wait in line at the price you select
at even being No. 1 in the line doesn't always mean the whole order will be filled that day
BUT Commsec prefers to sell between customers and badges the trade NXXT , i don't know if any other broker does that between clients orders ( but since it apparently isn't illegal , maybe they do )
now the trap is ... do you wait patiently ( and miss out on other opportunities ) or do you chase the price if it gets close ( i strongly resist the urge to do this ), but it is your trading strategy , do the best you can , for you
now depending on how much you love paperwork ( and ASX charges $55 to transfer each share holding to a different broker .. that is say all your BHP for the $55 , all your CBA for $55 etc etc )
another option is to open an account with a different broker and operate them in parallel ( i have two platforms and each has their good points and bad ) but the paperwork is a bit more complex , but it is an acceptable compromise for me