I was going to ask about this. I don't think it's been fixed in 1.3.03 yet. Playing around in my eagle taxi the last couple days I've killed over 120 pirates at RES and my progress bar did not move 1%. Most were mostly harmless, with a smattering of other ranks up to master, and I'm at master. So I'm assuming that I have to fight master and above to rank up, and maybe if I logged out and in again I could find a spawn with higher ranked opponents. I'll have to try that.
Worst part, I forgot I had 4 million cr in Eprire bounties and lost them fooling around in my taxi.
I think I'll go back to trading for now, and then go get my Vulture before trying combat for real again.