time-related uses of तक and से [StartTime↝Interval etc.]

[Aryaman Arora]

• मैं दो घंटों तक बैठा रहा।
  I two hours until sit-PRF CONT
  I kept sitting for two hours.
  Duration↝EndTime?
• कल तक काम कर।
  tomorrow until work do-IMP
  Keep doing the work until tomorrow.
  EndTime↝EndTime

These seem to be a temporal use of Extent, but what function fits them?

[Aryaman Arora]

• मैं दो घंटों से बैठा रहा।
  I two hours ABL sit-PRF CONT
  I have been sitting for two hours/since two hours ago.
  Duration↝StartTime? Duration↝Duration?
• कल से काम कर रहा है।
  tomorrow ABL work do CONT be-PRS
  I have been working since yesterday.
  StartTime↝StartTime

[Aryaman Arora]

From Dr. Schneider, 6/22/20

maybe better to treat the event duration as an inference, and “2 days” as metonymic for a point in time (2 days before/after now)
i think that would be StartTime~Interval and EndTime~Interval then