  The LCLS-II HE superconducting linac can produce multi-energy beams by
supporting multiple undulator lines simultaneously. This could be achieved by
using the cavity SRF tuner in the off-frequency detune mode. This off-frequency
operation method was tested in the verification cryomodule (vCM) and CM 1 at
Fermilab at 2 K. In both cases, the tuners achieved a frequency shift of
-565$\pm$80 kHz. This study will discuss cavity frequency during each step as
it is being assembled in the cryomodule string and finally when it is being
tested at 2 K. Tracking the cavity frequency helped enable the tuners to reach
this large frequency shift. The specific procedures of tuner setting during
assembly will be presented.
