Going off the new lore notes that tied significant campaign events to days of the week and in-game comments, the days of the week go:
victor's day & weaver's day have not been placed in relation to other days. however given ilumi is the goddess of the moon and the god of the sun's day is essentially our sunday, i would guess that weaver's day is equivalent of monday and victor's day is wednesday, but that's just a guess so.
the months of the year are also named after the shapers if trozemere is a pattern to judge by, which it probably is. more than likely we have 7 months in a year rather than 12.
given aramán seems to have pretty regular cycling annual seasons and not GRRM style mega seasons (as candle feast is the autumn equinox/a yearly holiday), we can probably assume something around 365 day year generally. at least until proven otherwise.
if we're basing it off that, that's 6 months with 52 days in it (7 weeks + 3 days) and one month with 53 (7 weeks + 4 days)
given autumn begins a little over midway through the month (30 trozemere 71), trozemere is likely the penultimate month of the year and the final month of the year will contain the winter solstice.
if i were going to make an educated stab at it, tansul and sylandri's months would encompass summer and spring, with rauwyn and ilumi possibly being the winter months due to gnomish and halfling homelands apparently being in the far north in colder climates
