That's great news! I'm tickled to death you found it so soon and nothing bad happened to it.
"and by the way, he actually eats very well. One fully thawed large rat once every 9 days. For his current size that is more than plenty"
Once again, please don't misunderstand me. I'm not trying to embarass you, criticize you, or anything like that.
I've been keeping snakes for 40 years, but I will admit that I have never had a jungle carpet python. My experience is limited to colubrids, burms, retics, and a few venomous species.
All snakes, reptiles, animals, humans, that get a full stomach from a fulfilling meal do not remain highly active afterwards. If your snake is as active after being fed as it was prior to feeding, it is not getting fed enough. I kid you not.
Now, some may cruise the cage for a minute or two afterwards but they'll quickly find a nice warm place to chill out & digest their meal. Any snake that puts forth enough effort to escape a weighted down lid within days of being fed is still hungry. I promise you. I assure you.
Our captives will teach us everything we need to know if we'll only observe & interpret their actions. I strongly suggest increasing the amount fed per feeding or feeding more often.
I'll bet that your JCP has quite a strong feeding response. Stronger than normal. I've got an 8ft - 7yr old female burm that I rescued and I pity the fool that would get between her & a prey item. Stems from being underfed.
Please, for the sake of your snake, and possibly your safety, at least think about what I'm saying.
I really am glad you found it. That's a heck of a feeling, re-capturing an escapee, isn't it? 
Take care & thanks for letting us know!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American

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