20 yrs English teacher here. Essentially, yes to the grammar points above.
It appears to me we have an idiomatic problem (beyond the mere grammatical construct). But fundamentally there's a semantic problem which leads to surprise and frustration.
"Light is making your body earlier/later" is not idiomatic bc it doesn't work conceptually as these words are commonly used.
Light cannot make a human body. And it cannot prevent a human body from moving, so it cannot make a body later. Conversely, it also cannot propel it, so it cannot make a body earlier. Bodies are necessarily 'embodied' things. Light is not embodied.
Therefore, readers feel confusion bc the concepts can't interact in the way it is written..
From my reading, there's a conflation of concepts in the statements under question. Bodies have various clocks which can be adjusted differently. But the statement collapses the two concepts into a single word.
Bodies are not clocks, but have and use various clocks. Clocks can be set earlier or later, slowed, or sped up. There's a lot of variability with clocks. The concept of a body has a different set of variability.
Therefore, it would add clarity if the statement "... is making your body earlier/later" were changed. As a final note: the progressive form further adds to the confusion, too. In English, it's a terribly awkward form to begin with. Many writers just say to avoid it entirely, if possible.
