CLIC\MODIFY TIME dut1
Modify the time constant DUT1 (in seconds) and recompute the phases ac-
cordingly. For very high accuracy astrometry, DUT1 may need to be ad-
justed afterwards to correct for irregularities for the earth rotation.
The "a priori" estimates may be wrong. Another case is the leap sec-
onds, if they are introduced asynchronously with the DUT1 constant...