Venus under her blanket of cloud and carbon, orbiting almost circular and with its axis almost upside down, does not notice seasons. But her orbits notice - barely, dealing with that 177.4° "obliquity" tilt. Satellites need the date of vernal equinox to fix Right Ascension of Ascending Node. Ascending Node of the sun's [apparent] orbit would be the day of vernal equinox; Right Ascension is something like longitude.
I found difficult to find other planets' equinoxes on account Google stuffs the results full of Earth. I did however get NASA on 2000. That vernal was 24 February 1930 UT. Two metonics ahead, at 2016 this should have been 19 February maybe 2130 UT. Yes we account for leapyears, of which Why Too Kay was one.
An autumnal equinox will come a half-meton from a vernal, so Venus should have had one 18 Feb 1600 UT on 2020. 49 days into that year; then another one early 274 days in, and (given the leap year on Earth) one 132 into 2021. Now we are set to get the vernal again!
During this tail-end of Synod D, then, about 20 January 2021 cometh the spring to Venus' orbital satellites.
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