Upgrade program

No. And there's no point either after all this time.

You've already paid for it, so there's no benefit in enrolling now. The upgrade Program lets you not pay all at once, but pay in monthly installments and upgrade after at least 12 months of payments and at least 6 months in the program.

If you've already paid for the iPhone, you can upgrade at any point in time and even start an Upgrade Program when you do choose upgrade.

No real point in enrolling now.

https://www.apple.com/shop/iphone/iphone-upgrade-program - "Get a new iPhone every year. You’re eligible to upgrade to a new iPhone once you’ve made 12 payments. Just trade in your current iPhone and start a new plan."

Not with the current phone you have, but you can start a new on at anytime if you are so inclined. I would wait for any new phone announcements before I considered starting.

Join the Upgrade Program:

iPhone Upgrade Program - Apple

Regards

Giulio