thank you all for your answers and the support. sorry for not replying so fast.
while recovering at home my dad had a blackout – he woke up on the bathroom floor and didn’t remember falling down. the reason was one of the stents got clogged. stent had to be replaced and since then a good month passed. jaundince faded and he received his photodynamic therapy. at the moment he feels pretty good and is adjusting to his new after sunset lifestyle.