I suspect so, since this kind of thing becomes more frequent as you go back in time. I think that's the same story for why some two-character words seem to have

I suspect so, since this kind of thing becomes more frequent as you go back in time. I think that's the same story for why some two-character words seem to have backwards word-ording, e.g. 日本に滞在する vs 在日する, or 米国へ渡る vs 渡米する. I've also noticed that readings seem to become more liberal in general. These days we tend to think of kanji having rigid associations to readings; however, you'll sometimes see some characters replacing semantically similar ones, despite the readings being different. I also suspect this flexibility is how Japanese acquired such a complicated mapping between it's written and spoken forms. Blah, blah blah. You get me on this subject and I can ramble endlessly. :)