I was at stage 10 of Road to LeMans, and had been using the Delorean when servicing or upgrading my car. At one point, i went forward 2 hours but forgot I was still online. When I came back to the present, I got a message I had missed the opportunity to get the 919 for free, but could still complete the event for 250,000$, which I did. When completed, the 919 stayed in my garage for 1 hour or so, then disappeared, and I had to buy it back for 950gc. Fortunately, it had kept all the upgrades previously bought.

So make sure to go offline if using the Delorean.

Using iOs 7, RR3 2.6.