356 cold cranking amps is a little low. I imagine the factory battery in your car is rated at 500-550 cca, meaning your battery is at about 70% of it’s capacity. I recommend replacement at 70%, because my experience has been that the downhill slide goes pretty quickly once they get below 70%.
Batteries can also fail immediately without warning once they get older, whether they test good or not. I recommend replacement if a battery is over 6 years old without bothering to test them. Here’s a case in point:
2 months ago I serviced my wife’s car. The battery was about 6 years old, but it tested at 85% capacity and started the car fine. Since we plan to trade the car in the spring, I decided to wait it out and not proactively replace it. A couple of weeks ago she went to a friend’s house on a Sunday morning for a few hours. Came out, dead. Battery hardly had enough juice to light the warning lights.
If a test shows that your battery is down to 356 cold cranking amps, I would replace it now. The goal is not to see how long a battery lasts, the goal is have a car that starts every single time.