I did configure mine, prior to switching to smart lock, to use my normal swipe pattern plus unlock nfc. Having removed all my registered rings leaving just the pin unlock in the nfc unlock I then had pattern + nfc ring password.

@MikeInSeattle said:

t will not re-lock it during or after the call, until after the device screen turns off.

Thanks Mike, I will give that a go today :)

Cheers Jason

i feel myself like ncfnoob :(

i changed the pin to a shorter one and tested it again. works. thanks

[SOLVED]