"ATTEMPTING" to parse the information provided...

"The Hoppes 9 is the original formula with ammonia that is highly corrosive. You want to make sure not to let it sit on non-metallic parts as it can cause damage to those parts.

So, do not allow Hoppe's Bore Cleaner to touch "non-metallic" parts (for any length of time).  I have known for years that Hoppe's can damage the finish on wood stocks.

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"Several copper-removing bore cleaners contain ammonium hydroxide, just as does Hoppe's Bench Rest #9 Copper Gun Bore Cleaner, Sweet's is a good example.  These bore cleaners warn not to leave the cleaner in a bore more than about 15-20 minutes before patching it out."

IMO, do not let any of these ammonia based products to remain in the barrel for more than 15-20 minutes.  Personally, other than oil, I only allow rifle-cleaning products to remain on metal for only a short length of time.  I then run barely damp patch with Ballistol to wipe away any remaining cleaner, followed by a dry then a damp patch with Ballistol, followed with a wipe-down of metal parts.

No, I am not a chemist.  What say you?

In the last decade or so I use Gunzilla in the barrel and wipe down the rest of the metal with Hoppes. Before this, it was all Hoppes except in my youth in Florida I used Rig. I only use oil on moving parts.

Guess I will have to check labels when and if I buy from now on, but all the Hoppe's that I have now is the old stuff, like me. Bought lots of 16 oz bottles when in the business. Never had a problem. No cure for old!!

There are 2 cleaning, preventative and rust preventative compounds that have never touched any of my firearms … Hoppe’s and Ballistol 
Eezox cleans, lubes and is a rust preventative…. Been through quarts of the product

With all due respect rkba2nd, I respectfully disagree with the position that a person should use whatever has worked in the past.
My point in bringing this up is to alert long time users of Hoppes that it is no longer recommended to leave the product in the bore. What has worked in the past (leaving the bore wet with Hoppes #9) is probably not a good idea with the product that is currently being sold under the "traditional" label.
Otherwise, I generally agree that if it aint broke, dont fix it. 
Joe S

My 32oz bottle of the good old stuff is about two thirds full so should last me about five to seven years. 

I did order a bottle of Ballistol. How is it used? Is it an oil or a solvent like Hoppes or must I have a seperate solvent and then use the Ballistol for rust prevention? 

Oh why did Hoppes have to fix what wasn't broken? Dratts! 

Here is the reply I got.  Logic by Grammarly?

Joe,

Thank you for contacting Bushnell Customer Support.   I’d be happy to help you with this question.   

Hello, Nothing has changed with Hoppes Solvent, maybe the packaging or label. You can still use it like you always have, just make sure to apply oil after words to your bore.

My dad always used G96. It had a pleasant smell that reminded me of bananas.

Maybe I order me some.