EEA Family Permit (for UK)

[Obi Kenobi]

My non-EEA partner (USA citizen) is currently applying for a EEA family permit to join me in UK and for that she's going through the application online. There's one step where it's requested to insert the EEA citizen's Permanent Residence card number and expire date. In order she can progress, we have one question for which we need an answer:

My Permanent Residence card doesn't show any expire date (or renewal date), only issue date. What is the expire date of my PR card that my partner can use in the application for the family permit?

Additional question:
I didn't apply yet for the EU Settlement Scheme but I can always do it before December 2020, from what I could understand. Is there any advantage for my partner to apply for a EU Settlement Scheme family permit instead of a EU familiy permit?

[NatCam]

I think you are mistaken. There must be an expiry date, unless it is a forgery. Look closer.