A Key Decade
Uranus-Pluto and Uranus-Neptune quadrature alignments appear only a few times per century. When they appear back-to-back we should expect magnitude level changes.
Since 1860 these alignments have occurred in the same or adjacent decades three times:
Between 2038 and 2049 we will see:
Uranus-90-Neptune; Uranus-180-Pluto