iOS 18 passcode inconsistencies between lock screen and passcode settings menu

TL;DR — iOS 18 on iPhone 16 Pro Max accepts an alphanumeric passcode on the lock screen, but fails for the settings menu. Known bug?

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On Friday, I took delivery of a new iPhone 16 Pro Max. During setup (with iCloud Restore), I used the same alphanumeric and symbols code I've used for years. However, it would allow me to unlock the phone but getting into the Passcode menu in Settings.app, it would fail. If I entered it via a Bluetooth keyboard, it worked.

Restart of the phone had little effect for this problem.

After attempting to reset the passcode in the Settings.app (after keyboard entry), I entered the same passcode using the Bluetooth keyboard and found that I could get in and out of the passcode settings menu, with both a hardware and software keyboard.

A few hours later, the phone hard locked itself due to the passcode being changed. The exact same passcode, no longer doesn't work on the lock screen, and the phone was pretty much inaccessible. I've had to factory reset and go through the entire process again, albeit, I'm using a similar numeric code only, until this issue can be rectified.

Is anyone else experiencing this? Seems pretty detrimental if it has the ability to render the phone completely inaccessible with no course of action than DFU.