The behavior is typical of a snake that is either too warm or a male that smells a female nearby this time of year. That behavior isn't really associated with a snake on its way out.

I would feed in the cage and offer a meal that is a little smaller than typical, such as a hopper or even fuzzy.

Double check temps with a temp gun or probe. If you have a female, put them in separate rooms.

Generally speaking, as a snake nears an age-related death, they will experience some pretty severe muscle wasting, no matter what they eat they lose muscle, they get sluggish, have problems shedding, and it becomes obvious.