Flamsteed used the star Sirius as a gauge to imply the false
correlation -

"... our clocks kept so good a correspondence with the Heavens that I
doubt it not but they would prove the revolutions of the Earth to be
isochronical..." Flamsteed

The contemporary version is slightly different,going to an
extragalactic source yet the false correlation remains the same -

"A stellar reference frame is time dependent because stars exhibit
detectable motions. For precise astrometric applications, a stellar
frame must specify, in addition to positions, an epoch and predicted
stellar motions. Imprecise knowledge of proper motion and/or parallax
limits the precision of stellar frames at epochs other than the mean
epoch of the catalogs. Extragalactic radio sources, on the other hand,
are assumed to be very distant (typical redshifts of about 1.0) and
thus should exhibit little or no detectable motion. A reference frame
defined by the positions of extragalactic radio sources may be said to
be a quasi-inertial frame (i.e., a frame nonrotating with respect to
an inertial frame) with little or no time dependency. "


The determination of whether axial rotation is constant or not is far
removed from the unsatisfactory premises applied by the IERS .

Judging from the bungling that went on last year with the IAU decision
to define 'planets' there is no responsible authority or open channel
to halt the misguided attempt to alter core astronomical principles
which keep clocks in sync with the axial cycle as a principle.

There is no central and responsible authority to recognise why
isolating axial rotation is important in order to discern if
variations in orbital speeds are occuring for climatological purposes.

Even with the orginal manuscripts and images of the Earth from
space,there is no responsible authority that can reverse the procedure
that links the axial cycle to a very distant sourse and return to a
focus on the central stellar reference through which the orginal
determination between the natural cycle (axial and orbital motions
combined ) and the human devised 24 hour cycle was devised.

What is happening is bad for everyone ,the great modifications of
timekeeping always involved astronomical, civil and religious
considerations and a intellectual standard which always mark the high
achievements of an age.For all the technological achievements of this
era ,the intuitive intelligence which distinguishes timekeeping and
structural astronomy does not exist isofar as clocks allied with
external references could never directly determine whether axial
rotation is constant or not.