Slurs within phrases

[rosearthur]

Is it up to the performer how they slur within a phrase? Can you do what sounds nice to you?

[PhilipL]

I have signed up to this forum just to ask a similar question about this topic. I am a (very) late returner to flute playing. Grade 5 or 6 at school (so long ago I don't remember which) and now past Grade 8 since I retired. No teacher due to the coronavirus at present to ask more detailed questions.

I am looking at Schubert's Introductions and Variations (always push yourself) and am trying to work out Variation 1 technique. I can't make out what is happening on the recordings I have, but am I right in assuming that only the notated slurs are slurred? The other notes are tongued?