Can I keep lights at superlumens until the end?

I'm growing with superlumens (1150W) and supplementing with Co2, but my question is about the light intensity, because in the last week or two I lower the co2 levels close to ambient (400-500) and I'm wondering if I should also lower the lights from superlumens to regular 1000W. Maybe it would be more accurate to talk about lumens, not wattage, but the point is the same. Could it be that if Co2 is down to normal, then it would be pointless to burn the lights at maximum power?

I want as big yield as possible of course, without reducing quality, but at the same time I don't want to waste electricity either. I'd like to keep my GPW up.

How to make sure if the plants are able to use up all that energy without extra Co2 in the end of flowering?

.. and please lets not talk about if superlumen mode is healthy for the bulb or not. I'm using a Philips doulbe ended bulb which doesn't lose lumen output per watt by overdriving it, and it is guaranteed to lose only 2% of lumens per full year of operation. Let's stay on topic pease

Is it true 1150W light? It will output a lot of heat. I just know there is 1000W HPS light.

I sometimes lower the intensity near the end of the flowering cycle.
The plants aren't really packing on weight anymore. They are just ripening.

In nature this happens to at the end of the season. The suns intensity goes down as well.