Thank you. I started briefly looking into possible remedies, but I haven't gotten too far, yet. Lots of "maybes", it seems; and the likely need to pursue them

Thank you. I started briefly looking into possible remedies, but I haven't gotten too far, yet. Lots of "maybes", it seems; and the likely need to pursue them in the "right" order so as not to have one rule out another. All from third parties. I haven't seen any useful, official response, yet -- except for some warranty replacements supposedly for units still under warranty. (But then, bye-bye data...) I'll have a look at your link, now. Appreciate it! P.S. "Heat"... I've rather pampered my 5X, but I did -- with all the intention of taking it in with me to the restaurant -- leave it in my car's dashboard compartment for an half hour to an hour, where I had atypically placed it while driving because the passenger seat was full of stuff. That compartment's door closed itself while driving due to shaking and gravity, and I forgot. It was cloudy when I went in, but sunnier when I came out, and the phone had gotten pretty warm while still running. Not melty warm, and it was idling during that time. My friends treat their phones far worse. It seemed to be fine, when I came out. But now that I think about it, a few days later, I experienced the bootloop. Then again, the phone had spontaneously restarted 2 or 3 times in the past few months, while I was using it. On those occasions, though, it promptly and successfully rebooted. The phone's only about 1.3 years old. I've heard some people have had success claiming a replacement, even out of the official warranty. Seems to be a matter of chance or/and reaching the right person.