You should wait till spring, I'm afraid, but it would be better not to remove any lower leaves until they start to look less than perfect rather than stripping off perfectly healthy leaves. Taking them off before they're ready means the part at the base is still fully live, and that's the cause of the whitening -hopefully there's no fungal infection going on. Because of the angle its growing at, any rain or snow will sit on that stem which could cause rotting, so ultimately, just stripping leaves off to reduce weight is not the answer, particularly as it gets longer over time. You might consider cutting it right down, but If it breaks, snaps or rots remove it at the base; there's a pup already growing at the base anyway, so you won't entirely lose the whole plant, just the taller part growing at right angles.

Thanks for the advice Bamboo. I've added a photo showing the plant about 2 months after it was originally planted. When I first bought it there was a section of green stem directly below the head where someone had removed several inches of healthy leaves. This green section gradually faded to the nice brown color you can see in the first photo. That's why I thought it was okay to cut off the healthy leaves.

Thanks for the comparison photo - this was a mature plant when you bought it, so its likely the leaves that had been removed were naturally past their best over time, rather than being removed when perfectly healthy.

The more healthy leaves that you can leave on the plant, the healthier and stronger it will be. In snowy weather, I would look at it every morning, and if there is a heavy load of snow, grasp it about where those leaves had been cut off recently, and give it a brisk, brief shake.

Thanks everyone for the advice. I've added a pole to keep the plant upright as you can see in the updated photo above. It looks much better now that it is not leaning over. I will avoid removing health leaves in the future.