Originally Posted by Unregistered

An official notification will only come to your P if you accept an offer in HRMS.

But it is a basic courtesy to inform your P and RO that you are intending to apply and there is a possibility that you will leave, should you be offered a position elsewhere. Unless you are for some reason completely not on talking terms with your P, you really should give him/her a heads up first.

It's quite rude to the P if he/she finds out first from another P or a Branch Head about your application, but radio silence from you. Or worse, suddenly receive a HRMS notification of your new posting out of the blue.