I will be direct and honest, but bear with me.
This IS a good question but, in my eyes, also an indirect signal that you need to get your “rhytmic auto pilot” to a more robust level.
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Make sure your strumming foundation is solid and on auto polit, this will actually reduce concious wondering about this. It IS a good question but it is something we do unconciously because we focus on keeping the rhythm and timing in both physical and mental ways (feeling it, nodding, tapping, counting, percussive hits, etc)
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Regarding your experience, remain self-ciritical and record yourself and use rhytmic help. A metronome, drum track, a soudn that you loop…whatever you feel comfortable with. Prime directive should be: Can I keep up at all, no matter what the speed is? When we haven’t engrained the rhytmic timing enough, we tend to focus so much on playing the right notes, you might lose track of the rhythm. This is better observed when checking a recording of yourself.
More about this in my “Community tip” article about auto-pilot:
Meanwhile, get your strumming in. Not only is that the bottom layer of your song, it is the most important one. when thing go awry in the upper parts like melody, embellishments and decorations, you need to be able to fall back to that mid song.
Yes, many will hear me echo; “rhythm is king” 
Bottom line is, if you want to FEEL FREE at a certain point, to play the notes you feel like playing at THAT particular moment, you need the brain power to do so and not be occupied with things like rhytm and how to play it.
Not to sound crude or anything but I believe this:
When you have trained your changes strumming well enough, you do your well timed changes for fingerstyle on auto-pilot as well and this wouldn’t be a concious question to ask