Article (as of right now) states that the current A17 Pro is manufactured on N3E. I don't think that's right. It was the very first commercial 3nm chip so at the time of release it was referred to as being a N3B product by the techosphere in general.
Now there were also rumors prior to release that a different A17 would be made on N3E later on, however I don't recall reading anywhere that such plans have reached fruition.
This was my understanding too, that the A17 Pro was manufactured on the more expensive N3B process (with lower yield).
As with the M3 it would not be offered after production of the iPhone 15 Pro was ceased - it would be too costly to continue manufacturing on the N3B process for potentially years as the iPhone 16 moves down the tiers.
Obviously this would leave Apple in a pickle as the iPhone 14 and 15 used a version of the Pro tier model CPU from the generation before (which had an extra GPU core).
The 15 uses an A16 CPU which comes with just 6Gb RAM so it probably couldn't be used again as it would be 2 generations old and without sufficient RAM to run the Apple Intelligence by Apple's own declaration.
Therefore there's 2 options:
1. The A17Pro gets a do-over on the N3E process and gets used in the iPhone 16. They'd either get to call it A17 (not pro) or the article suggests a CPU called A18 (but it's really an A17 on the 'new' process). Why would the marketing folks care what it's called though unless they wanted people to be confident it could cope with Apple Intelligence?
2. Apple do an 'A18 Pro' CPU for iPhone 18 Pro, and create a real but binned A18 (non Pro) for the iPhone 16 - all on the N3E process. I think this is more likely - and Apple could then return to the iPhone 17 with a less binned A18 next year. Yes, add a GPU core back
Imagine also that the AppleTV could get the (binned?) A18 as well, especially if Apple decide it can be used to hand off AI requests from devices such as Home Hub and Apple Watch, and older iPhones if the user is at home.