There's a few upgrade posts in the grand "Shorten PAL approval times" thread. Yes, you will get called. No, there's no 28 day wait time. RPAL is not another license, it's an endorsement to your current one, like adding air brakes to your drivers license.
I don't recall 100% (stopped following the thread) but I believe most were getting "approved" in about 10 days from them entering it into the system, or about 21 days after they get the papers.