So by 55 days do you mean from seed sprouting or 55 days of flowering? If of flowering then yes another 3 weeks maybe 4. And the dark green client make me think it's anything but the color of your strain. Some run a dark color. And I wouldn't say you're going to get airry buds yet at all. Still plenty of time to add weight.
The light situation, you say 338watts. So that's 37.5 w per sq ft. Not bad, 50 is the optimum watt per sq ft. , 30 is the minimum. If you could find another 75 true watts I think you will gain yeild. Look on Amazon or eBay and I'm sure for $50-75 you can find something to help you out. Or on Craigslist, FB marketplace, or the app Offer up. I see great deals on lights there all the time. Lots of true 50-100 w lights for like $30-50. Just a thought.