I don't believe they have, officially. They have been quietly trialling faster speeds in the field for years now, and assuming that the speed test you've done is accurate, I'm guessing that you're benefiting from one of these trials. If that's the case, make the most of it because there's a good chance it'll disappear as quickly and quietly as it arrived.
I'd guess that the plan is to launch a faster 1.5 or 2.2 Gbps tier as they've already trialled faster download in many areas now, and when that goes live as a product it will feature a higher price, and the 100 Mbps upload. You'll certainly hear about it when they want you to get your wallet out, and I'll wager they won't be giving 100Mbps upload as a freebie.