Equestrian Timekeeping

edit: 11/18/15 - adding a few extra notes, mostly for my future reference.

Over the years I've seen some speculation and theories about the calendar Equestria uses, like how many days are in a year/month/week, what they would call them, etc. etc. etc.

Generally, I'm somewhat adverse to outright inventing lore details when I can use or expand upon those already stated in the show, but in this case there is very little to go off of. I'm going to list what I know about Equestrian timekeeping from canon (hopefully I'm not missing anything):

* There is winter, spring, summer, and autumn seasons. I'm making the bold assumption that these are the only seasons.
* Ponies control the seasons directly, at least in Equestria, through activities such as Winter Wrap-up.
* Winter is 3 months. I am making the assumption that the other seasons are also 3 months.
* Twilight's planner in Lesson Zero had 24 slots per page. I am making the assumption that these are hourly slots instead of daily slots.
* One of the days of the week is called Tuesday, and a week does not have 10 days (both from Lesson Zero).
edit: 11/18/15 - Sunday is also mentioned in Read It and Weep.

I may have missed a few details. For instance, I can't recall if they've ever mentioned the name of a month, or the names of other days of the week. Since there's so little to work with, I've invented my own calendar for use in my stories here. Warning: gratuitous head-canon ahead.

I'm ignoring Tuesday as a translation to our English. It's hardly plot critical to the show, and it lets me be more consistent in my naming scheme.

12 Months to a year, 3 per season. The new year starts with the Summer Sun celebration, which also marks the beginning of Summer. Each month is 24 days, with 3 weeks of 8 days each (6 work days, 2 days weekend)

The days of the week are:

Solys (Weekend)
Benifys
Lusys
Liberys
Veritys
Fidys
Amicys (Half-Workday)
Lunys (Weekend)

***
edit: 11/18/15 - I find 7 day weeks less troublesome and less likely to be contradicted by some minor details now. If I use this system months have 4 7-day weeks, Amicys will be removed, the 5 subordinate elements have been roughly associated to the deities of the remaining days, and the new order is:

Lunys (moon day)
Veritys (honesty/tiw day)
Benifys (kindess/woden day
Fidys (loyalty/thor day)
Lusys (laughter/frigg day)
Liberys (generosity/saturn day)
Solys (sun day)

Saturn day and Sun day are the weekend, natch. More dichotomy between Luna and Celestia's days is a nice bonus. 1st of the month is always a Monday, last is always Sunday.
***

From start of the year to the end, the months are (edit: 11/18/15 - dates in new month system in parens, also includes shorthand (shorthoof?) for months):

(Start of new Year)
Sol (Beginning of Summer, Named in Honor of the Sun, Celestia's official birthday is Sol 1 (Inv 28))
Vita (Vit)
Light (Lig)
Feydawn (Fey, Beginning of Autumn, Nightmare Night on Feydawn 16 (Fey 20))
Thauma (Tha, Transition from Feydawn marked by the leaves of tree all having changed color.)
Descent (Des)
Selena (Sel, Named in Honor of Luna, Descent 24/Selena 1 (Des 27/28) is the longest night of the year)
Hearth (Hea, Celebration of Equestria's founding on Hearth 15 (Hth 20))
Dream (Dre)
Revenio (Rev, Beginning of Spring, Hearts and Hooves day on Revenio 23 (Rev 26))
Heart (Hrt)
Invictus (Inv, Summer Sun Celebration on Invictus 24/Sol 1 (Inv 27/28), Luna's official birthday is Invictus 24 (Sel 1))

edit: 11/18/15 - I'm somewhat tickled by the interesting timing I've ended up with here: Revenio ("return/come back") is 11 months after Heart, which starts just after Hearts and Hooves day. I think the general assumption is that Equestrians roughly follow the 11 month gestation period of horses, right?

From this, every date is always on the same day of the week, each year. Sol 1 is always on Solys (or Sunday) (Monday now with edits), Nightmare Night is always on Lunys (Saturday), and Hearts and Hooves day is always on Amicys (Friday/Half-Workday) (Friday now with edits)

After messing around with a Latin translator for a while, I came up with the bastardized day names above. I decided -ys would be a good suffix for days, because it looks and sounds neat to me. Solys = sun day, Lunys = moon day, benifys - amicys are taken from Latin words related to the 5 elements of harmony and friendship (not magic), truncated with a -ys tacked on.

Nightmare Night is on the Saturday equivalent to give everypony a full day to set things up and enjoy the holiday and ensuing sugar crash the next day. Hearts and Hooves is on the half-day Friday equivalent to give ponies a nice long weekend to enjoy each other's company (it is not a weekend date because the Crusaders do have class that day, but it seems rather short since they have much of the day to concoct their plans for Cheerilee. Holiday early release, or standard for that day of the week? You decide!)
edit: 11/18/15 - This paragraph is not very relevant on the new system.

Any thoughts are appreciated. Criticisms? Expansions? Suggestions? Revisions? Did I miss some canon details?

Also, feel free to use part or all of these ideas in your own creative ventures.