People commonly store brews 1-2 years, longer happens frequently too but mainly only on high 10%+ ABV.
So yes, you're fine. In fact most swear by aging their beers ~3-4 months to get maximum flavor. (With exceptions to the rule like wheats)
Edit: Just in case you forgot. Remember to purge the tank of air after kegging it too, to maximize shelf life. Put pressure on, turn off co2, let it sit a minute or two, release the co2/air, and then re-pressurize.