  We attempt to understand the CFT$_1$ structure underlying (2+1)D gravity in
flat spacetime via dimensional reduction. We observe that under superrotation,
the hyperbolic (and dS$_2$) slices of flat spacetime transform to
asymptotically (A)dS$_2$ slices. We consider a wedge region bounded by two such
surfaces as End-of-the-World branes and employ Wedge holography to perform
holographic reduction. We show that once we consider fluctuating branes, the
localised theory on the branes is Jackiw-Teitelboim (JT) theory. Finally, using
the dual description of JT, we derive an 1D Schwarzian theory at the spatial
slice of null infinity. In this dual Celestial (nearly) CFT, the superrotation
mode of 3D plays the role of the Schwarzian derivative of the boundary time
reparametrization mode.
