See my Pentax K1 wish list at B&H Photo.
Update Sept 2016: Pentax adds EFC shutter firmware update.
Pentax K1 behavior should be IDENTICAL to the K3 II, so for more details, see the discussion of the Pentax K3 II behavior with/without Live View.
Pentax USA via Pentax Japan confirms that there is no EFC shutter option in the Pentax K3 II or Pentax K1.
However, there is one exception: SuperResolution pixel shift mode uses EFC shutter. SuperResolution pixel shift mode is the ONLY exposure situation in which EFC shutter is used: Live View does not, self timer does not, etc.
So for example if a 300mm is on the camera and Live View is in use—no EFC option and the risk of blur from the shutter exists, not to mention the disconcerting bang-bang behavior described in the next paragraph.
There remain disconcerting behavioral quirks in Live View mode even for pixel shift and even when already in LiveView, such as banging the mirror down/up, opening the shutter, then doing the self timer. Or the ill-considered ability to use pixel shift mode without the self timer (resulting in guaranteed checkerboarding problems). Or banging the mirror down/up just to see info when in Live View mode. Or disabling the self timer every power on/off (this at least can be defeated). Or refusing to operate if the card doesn’t have an image folder (“Card not formatted”). Or mysteriously failing to record half a dozen images (no warning of any error, seen on 645Z and K3 II so surely a firmware bug). These issues are not there on Canon or Nikon. It makes the whole Pentax experience feel unstable, if nothing else.
As much as I admire the Ricoh-Pentax design thinking in terms of innovative features, when critical features like an EFC shutter are omitted, it makes it a lot harder to take the camera seriously. Regrettably, these design issues may relegate the K1 to a specialty niche tool, that is, a superb studio camera for still-life photography. Even then the lens selection is problematic: in spite of all the Pentax lenses out there, many are mediocre and there is no Zeiss DSLR lens support.