Client auto selection of Multi-version/optimized versions vs auto-quality?

Hopefully not too messy of a question.
When a remote client initiates a playback, and the source is greater then the bitrate allowed for streaming, is a transcode the only thing Plex will do automatically?

In a roundabout way I’m really asking a set of related questions:

  • If you have an optimized version, will it get auto-selected in that scenario over a dynamic transcode
  • If you have multiple versions, and one fits the criteria the client asks for, will it get selected automatically?
    i.e. if base version is 1080P@12Mbps, but a 720P@4Mbps exists, and client requests or is only allowed 4Mbps, does it still transcode the 1080P, or does it use the existing 720P? (really, same question as optimized version, only pre-providing it vs haivng Plex create it)
  • those 2 questions are in a sense asking if there’s any point having multiple versions if the end user doesn’t know to select from them.

Are optimized versions automatically selected, or only manually selected? I gathered from searches it used to present the option(which I sorta recall) but doesn’t anymore. I think it’d be useful for it to autoselect, but might be too much to ask to get other people I’ve granted access to remember to do (select res/bitrate or from optimized).

Thanks!