The description says “Gained at least 12 positions in any Multiplayer race”.
meaning ≥12, right?
Well, I gained exactly 12 positions but it didn’t unlock. 
If it only unlocks when 13 or more posititions are gained, then it should say “more than 12” or “at least 13”.
Hi All
I have also created a ticked, but I am unable to unlock this achievement in featured multiplayer lobbies. I have tried numerous times, with between 13 an 19 positions advanced.
These are links to some of my feeds with the screenshots, or just look at my profiles.
I have also tried sync options, even deleted and redownloaded my profile from the console:
https://support.xbox.com/en-US/help/games-apps/achievements/troubleshoot-achievements-challenges
I fear this is permanently glitched for my account.
Anyone with any good advice beyond what I already tried.
Ticket says to wait for 72 hours now after the restart sync. Did another run, and got from 22 to 3 in a full lobby of 24 people, so 19 in advanced as it said in last screenshot on my profile.
Please write if you come up with a fix, or can I expect help from Turn10 ?
I seems the achievement is not unlocking if someone quits before the timer ends or all has passed the finish line.
Since this is a 2 minute timer, and in public people are often leaving and joining other sessions, this makes the achievement incredible difficult to acquire legit in public scenarios.
Either update the description so this information is public, or even better just remove the restriction and perform the count at the end screen of the race, disregard less if any player quit during the race
I also can’t unlock this. Just gained 12 and once again no achievement. No idea what to do.
I have already submitted a ticket.
Just finished an incredible race with 12 positions gained for the win, no penalties. As the achievement states, gain at least 12 positions.
As can be seen, 12 positions were gained from 13th to 1st and the achievement was not awarded.
Really takes the wind out of your sails after putting in the work to tune and test.
Same issue for me. I also opened a ticket, but got an unhelpful auto reply as an answer.
Same here, bit gutting that one to be honest as I thought it was one of the ones I’d really struggle to get but managed it somehow. Don’t suppose there’s any chance it will be awarded retrospectively as there don’t appear to be any race history stats.
Mine also didn’t unlock for gaining 12 positions, only unlocked when i gained 13 positions so maybe that achievement description isn’t correct.
Seems like it. Unlocked for me when I gained 14! 
Unlocked for gaining 15 positions. Seems like the 13+ positions is the actual requirement.
There has been 2 patches and they still haven’t fixed the issue. *sad Forza player noises*
Same issue for me. I have gained between 13 and 19 places multiple times and it still won’t unlock
For me the same, i gained multiple times more than 12 positions and nothing popped for me.
Same, gained often more than 12 positions and nothing, please fix this.
Just gained 12 places in the birth of GP spec event multiplayer but didn’t get the achievement. Didn’t take a screenshot but a bit disappointing.
13 unlocked it for me! 12 did not
We are closing out this issue. The developers have noted this issue as Fixed as of Update 3.0 on 12.12.23
