We will be doing the Camino starting from Sarria the last week of May. Is it likely that they will swing the botafumiero during the daily Pilgrims' Mass at that time?
No. At that time because the interminable obras will still be ongoing.
At other times, scheduled or not, the bota will be swung for a suitable payment in advance. In early 2009 €500 from a Russian tour group had it swinging.
The phrase " the bota will be swung for a suitable payment in advance" sounds really bad.