When is Doctor Strange actually set?

The films from the Marvel Cinematic Universe (MCU) are usually set roughly around the time they are released (barring flashbacks) or at least in a chronological order congruent to their release order. They often reference events from past MCU films or foreshadow future films (e.g. in post-credits scenes). However, with Doctor Strange there seem to be some discrepancies with this approach.

• At first, it seemed a reasonable assumption. There even seems to be a reference to Rhodie's accident in Captain America: Civil War, when his assistent presents Dr. Strange with some potential patients and mentions something similar to (quoting from memory)

  an Air Force Colonel paralyzed from the spine in a special protective suit.

  And then there's also the post-credits scene with Thor, which seems to be a foreshadowing of the upcoming Thor: Ragnarök.

• However, someone pointed out, that the reference to the paralyzed Colonel might as well refer to the guy we see in Justin Hammer's failed attempt at copying the Iron Man suit in Iron Man 2. Besides that, we don't exactly know how much time actually passes in Doctor Strange, considering how he seems to go through significant rehab treatment and spends his fortune trying various healing methods before getting involved with sorcery (let alone the time he actually spends studying at Kamar-Taj).

• And then I noticed something really interesting in Captain America: The Winter Soldier, where Sitwell is interrogated about HYDRA's plans and says:

  Zola's algorithm is a program for choosing Insight's targets...You! A TV anchor in Cairo, the Under Secretary of Defense, a high school Valedictorian in Iowa City, Bruce Banner, Stephen Strange, anyone who's a threat to HYDRA.

  And I wondered if Dr. Strange actually already had his magic powers at the time of The Winter Soldier. Or why else would he be a threat to HYDRA, as much as we know he's just a really good neurosurgeon.

• Then there's also the tidbit that for a Phase 3 movie the film seems a quite traditional origin story, resulting from the possibility that Dr. Strange's inclusion in the MCU might have been decided much later than the other plans for the MCU, based on its overall success and the motivation to take higher risks with less mainstream-famous characters. This might either point to an earlier setting of the film. Or it might as well render the above statement in The Winter Soldier somewhat of a premature blabbing which is now being retconned.

So is there any secured information about the setting of Doctor Strange within the MCU's timeline or at least more conclusive hints from this or other MCU movies? If not or if we are to assume it's released roughly chronologically, then what explains the above statement from The Winter Soldier about Stephen Strange being a threat to HYDRA before his involvement with magic? Or was this really just a throwaway comic reference without much thought or significance put into it?