Upgrade to PE on Level flight using Avios?
 

I'm booked on a long haul flight out of BCN, with IB flight number but operated by Level. The outbound is flexible economy (L fare) and the return is premium economy. I'm trying to figure out whether I can upgrade the outbound to PE using Avios (from my Iberia Plus account). I can't find any option to upgrade (whether for cash or miles) when I manage my booking. Is it possible for Level flights?

You need to be in Y, B or H to upgrade using Avios. Even then I have my doubts that it can be done on LEVEL.

You might receive a promotional cash offer to upgrade during OLCI or maybe at some point prior when managing your booking.

It all depends
 

I have got avíos offers for upgrade in long haul, from T (PE), in different moments. You need to open session in you account frequently and check It, because It is offer based, not on demand.

My husband and my sister got offers to.

And years ago I was able to upgrade with email cash offers at check in.

The topic is asking to upgrade to PE, on LEVEL, from than from PE to business, which LEVEL doesn't have.

I know, but I was only giving examples of the process. And that It is not límited by your original fare.

It is not limited by your original fare only when IB decides to offer promotional upgrades.

When you want to confirm something on your own timeline, you have to follow the formal rules, as you sort of mention.