WLP838 attenuation?

I am hoping to tap into some group knowledge relating to the attenuation of WLP838 (Southern German Lager).

Most of my experience comes from using WLP830, but I wanted to experiment with some other lager strains and people seemed to like this strain for it’s maltiness. I’ve been using my standard procedures which involve using a 1.8L starter (stir plate), in line aeration with regular air, and fermentation at 51F for two weeks followed by about 1 week at my garage ambient temp (~60F) before transferring to keg. What I’ve been finding is that the main fermentation stops about 5-6 points higher than my fast fermentation test (example being helles where main fermentation went from 1.050 → 1.016 while the FFT went to 1.010. My FFT was done with the residue of my starter at room temperature. The flavor of the main fermentation was good, malty, and didn’t seem particularly sweet. But the difference in attenuation seemed larger than I’ve seen for WLP830.

Does this match other people’s experience? If not, any particular place to start? (switch to oxygen, higher temps, etc?)

Thank you all for your input!

Cheers,

Jim