Travelling - or not travelling?

[Harper]

David, I'm a novice, albiet not young, referee learning to referee under FIBA rules in Canada. Your description of the play has me a little confused so , for my own understanding, I'll try to break it down.
The player receiving the ball catches the ball on one foot ( lets assume the right foot )establishing it as the pivot foot inside the 3 point arc.
The player then places the non pivot foot ( left foot under my assumption ) outside the 3 point arc.
The pivot foot is lifted and a shot is attempted.
My interpretation of the rules is that if a field goal is attempted while standing or jumping off solely the non pivot ( left ) leg prior to touching the pivot foot back down then there is no travel and the attempt would be legitimate. However, if the original pivot foot ( right foot )touches the floor, presumably to attempt a jump shot for example, then it is in fact a travel violation precluding any field goal attempt.
Any feedback on my assessment of David's case scenario would be greatly appreciated