FS, you're funny
No, I haven't talked to your coach and we didn't have a mindmeld
They're my personal experience. I helped several adults in the rink to do LFI 3 and that's why I remembered what to do (and what not to do) when doing LFI 3.
When you're holding your LFI longer, it gives you time to bend your knee and balance yourself. If your knee is bent, you'll be skating in a deep curve. Eventually, the rocker will kind of "clicked" and the turn happens. At that precise moment, it's the "UP" moment.
During the "UP" moment, pull your arms back to the sides of your body. Don't swing your arms like a wind mill. That will totally pull you into a over the top deep curve and makes it hard to check after the turn.
Instead, the shoulder should be stable, just bring your arms back to your sides in a scissor motion. Now, you are kind of like standing up with your arms on your sides like a good little soldier. Remember, this all happens very fast (in less than a second). I'm just doing a slow-mo here. A common problem at this moment is the "shoulder". Don't let your left shoulder swing too far ahead to force the 3 turn.
Right after the turn, "CHECK". And remember to bend your knee (and in strong check position) so you can finish your 3 turn in style!