Available_date vs. unlocked_date, tracking SRS events?

Hi all:

Two quick API questions:

  1. Both unlocked_date and available_date are defined whenever there is data in the user_specific section for a particular radical/kanji/vocab.

    unlocked_date is always before available_date, so I assume it’s the timestamp that the item was first shown in a lesson.

    But what is available_date?
  2. Is it possible to get dates on historical SRS events via the API?  IE, track when a given item went from Apprentice->Guru (or vice versa)?
Thanks!  I’m working a little WaniKani progress visualization app in honor of my one year wanikani anniversary.  I’ll share it here once it’s done.

available_date is the next review date.
There is no historical info via the API, other than unlocked_date.

Perfect, thanks.  It’s a little confusing that the api still supplies an available_date, even if the item in question has been burned.

FYI, unlocked_date is goofy on most people’s accounts for levels 2 and 3.  It’s related to the paywall and how WK marks items for upcoming unlock.