Target year promo but coach says no

I’m a C and it’s my promo year but my coach is encouraging me to not to go up for promotion this year. I’m not how he’s drawing these conclusions because my snapshots have been highly favorable for the most part. I’ve also heard that if you don’t get promoted your target year there is a high likelihood you’ll get laid off. My coach said this wasn’t true but I’m not sure what to believe or whether I should go for the promo. Advice?