Quartz 48, November 2019, is online at:
http://quartz.chessproblems.ca/pdf/48/Quartz48.pdf
By Paul Rãican:
The contest has one section: 1. Proof games with #color condition.
It is admitted, but not necessary, to add at most one other condition (but not fairy pieces). The tourney is informal. Send problems to the judge, until the 1st February 2020. Judge: P. Rãican.
#color (or simply #c) was introduced by Andrey Frolkin and Chris Tylor in feenschach 212/2015.
Definition: After a checkmate, the colour of the mating piece(s) is changed and the game resumes, if a legal position results. In a first phase, the authors introduced this condition in helpmates, but then, they also used it in proof games.
See, e.g., the problem No.1374 from Julias fairies. The genre may be tested by Jacobi, with condition #c.