WLP002 and Wort Fermentibility

Hey guys, I’ve been using WLP002 a lot lately (hadn’t used it in a long time until just recently). And I am trying to gauge the attenuation I should expect from this beer:

92% Maris Otter
8% British Crystal 65L

Mashed at 148F, no mashout

My guess has been 72-74%, but I don’t really know. Anyone have a better idea than I do?