Interesting-flight planning to Nice when going to Palma. I believe Monarch might have done that much more recently ( but some years ago) when operating A321s to Ovda- planning the return to Brussels and then continuing to Luton when fuel was okay to do that.
Would such a practice be frowned on today?
I think you’all find the practice was frowned on when BAF did it......amazing how blind an FOI could be.
There is absolutely nothing wrong with in-flight refiling of a flight plan to a further destination. It is a common, perfectly legal practice. It is all based on the percentage of contingency fuel required to be carried. On a long flight this can be quite large and put the aircraft over its max take-off mass, so you file a flightplan to a nearer destination where the contingency fuel requirement is lower so you are below max T/O mass. Once in the air and nearing the filed destination you replan to carry on to your intended destination. Because the remaining distance to go is much shorter the contingency fuel requirement is now much less so the contingency you loaded for the nearer "destination" is now enough to carry on to your intended destination.