Maybe this would test that hypothesis. Try looking with a magnifying glass and see ify ou can see any air bubbles in the printed filament?
Thanks so much for your ongoing input. You know what it’s like when you’re chasing these probs - when on your own there is no one to vent to. I’m going to stick it out and wait for a new spool to be fully dried before I go chasing any more settings. If that doesn’t work, I’ll switch out a .6 nozzle in one of the other printers and try that to rule out hardware.
Please do let us know how it works out for you. We’re all learning from each other, but it only works if people report back. That helps not only everyone in the original conversation, but people with the same problem as you who find this thread in the future. Then they’ll know what worked for a solution.
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I reckon that’s a yes. It’s a lot clearer looking through a magnifying glass, but I think its still visible with zoomed in iphone.
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It’s hard to make out from the photo, but I’ll take your word for it. Post a benchy or something after you dry it out, and if it looks good we’ll close the chapter on this…assuming your primary print works like you want it to, of course. 
BTW, in case you were unaware, for as little as $30 (probably even less on aliexpress), digital microscopes have become so amazingly inexpensive that they’re a good tool to have around, even if you rarely use it. Lets you take photos onto an SD card and share them for situations like this. Or, in other realms, if you have to read part numbers of an IC chip, or find solder bridges or milling errors, it’s a real godsend. Some people buy lenses for their cell phone, but for the same money or less, you can get a complete digital microscope that probably works a whole lot better.
OK just for interests sake, still waiting for the filament to dry but being confident that it was not my filament being wet anyway, I decided to try the same print with PET-G. Standard profile and my go-to. Guess what, exact same problem. I print this stuff 24/7 across two printers!
Now what ???
I think I’m going to change the complete hotend, run cals again, and beyond that I think it’s time for a support ticket.
It’s definitely the cooling problem. The picture shows that the top layer is sinking into the infill. Get the fans up high, try a lower printing temperature, open the door… Just make sure that the bridging is solid at the top layer.
Isn’t that now a bandaid just chasing a problem that didn’t exist to begin with. I appreciate the input, I really do, but I’m more interested at this point in finding the source of the problem.
I don’t know whether it will work or not, but if you’ve run out of ideas the “nuclear option” is simple enough, fast enough, and easy enough that it might be worth a try. The idea is to take a perfectly fresh installation of the slicer (maybe on a different computer to guarantee that it’s clean) and then try the print again with one of the generic profiles. The idea behind it is that somehow, without meaning to, some slicer settings somewhere got changed, either unintentionally or without you remembering, and the nuclear option gets you back to something that prints reasonably, even if it’s not optimally.
The other long-shot some people propose is to do a “mesh repair” on your model, even if the slicer isn’t complaining or asking for one. I think that may have worked for me, maybe once. It’s when you’re really scraping the barrel for ideas that one reaches for that one. Probably skip this one, since your benchy is a different model and is having problems too.
Of course, make sure you have all the latest updates installed. I know it sounds too basic to be worth mentioning, but on a different thread recently a seemingly very smart guy had overlooked that and got caught with his pants down. He even very astutely analyzed the problem and reported it as a slicer bug to BBL, and to their credit they responded in less than 24 hours that it had already been fixed and that he should use the current version:
Print dramatically failed, never seen before
As to whether/if any of this makes sense to contemplate, given that your stuff was working just recently and now no longer does, maybe it doesn’t. It’s more in the hail-Mary category. Process of elimination is the fall back when all else fails, but at least none of this is hard to do. Anyhow, I’ll let you be the judge of whether any of it is worth trying or not.
And now I’m out of ideas too!
Edit: Actually, one last idea, load some PLA and slice a benchy and print it with that. If it still looks bad, then try the pre-sliced bench that comes built into the printer. If that prints well, then you can be sure it’s a slicer problem and not a problem with the machine. You have 3 machines all acting up, so it almost certainly isn’t, but again, it’s something easy to try that delivers a hard datapoint and not just theorizing.
Wish I could have been more helpful and that we could have nailed it already. It has me very curious now as to exactly what went wrong. Good luck!
This could be resolved. I’ve just successfully printed the same part now in PET-G. Now switching back to PET-CF to be sure. Only change was brand new hotend, and transferred a used but different fan and brand new thermistor. Then ran Machine Cal again.
Stay tuned.
Hard to believe hey? Look at the difference:
I guess we can call this resolved and it was some sort of gremlin in the hotend assembly somewhere. A mystery. I’ve kept the components and labelled them though so I can figure it out on a rainy day.
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Back to production - fingers crossed! But sincerely, thanks so much to those that put time into responding and making suggestions. I did learn some new things along the way. Much appreciated 
I was having the same problem and it blows me away that in 52 posts here no one even mentioned anything about hardware failing! Mine was a worn out nozzle and a bad fan. I had months of great prints and all of a sudden it went downhill over a week and then days and then horrible. Why would anyone think this is a setting problem lol?
I don’t think any of us get in there and bang the keys around changing everything. I know this is an old post but people still see these when they’re looking for help with their problems. I know Bambu printers are good but they do have parts that fail regardless of how new or old they are or what filament you use.
Does it even make sense that if it’s a cooling issue that it could be the fan? Possibly? Lol.