UVM extension returns all available verification methods instead of the actual method used.

I'm trying to limit the authentication to only allow fingerprint through on my device and not pin or pattern. On a phone device at least I don't believe pin/pattern to be secure as parents are always giving out the pin to their children and pattern leaves a smudge on a dirty screen meaning it's easily visible in the correct light (and also given out to children).

I was hoping the UVM extension would be able to help but it returns the same flags (fingerprint, pin, pattern) every time, no matter which verification method I've used. This is blocking me implementing passwordless authentication on my site (credit cards (PCI compliant) are stored so future purchases are simpler). Is that intended or a bug?