The process for filing an H1B “transfer” petition is the same as the process for filing a new H1B petition, since each H1B petition is employer specific. Therefore, it generally takes the same amount of time to process the H1B petition.
The main difference between an H1B “transfer” and a new H1B petition is that one who already holds an H1B status is generally not subject to the H1B cap and does not need to wait until October 1st to start working, if the H1B quota has been used up for that fiscal year.