It is easy to find information on the Internet regarding EU Air Travel flight compensation. However I am interested in being prepared to exercise my right to be taken care off (Article 9th of CE Regulation No 261/2004) during huge flight delays while the situation is taking place.
Some examples of situations where I do not know what am I entitled to:
Boarding completed and plane waiting at gate for takeoff slot - passengers must be seated with seat belts on. After how much much waiting time should passengers be allowed to stand up, such as for taking snacks of stowed luggage of to use the bathroom?
Boarding completed; plane waits for hours before departure; low cost carrier (doesn't normally offer free meals of refreshments inside the plane). After how much time should the airline provide refreshments (if at all)? After how much time should a need for accommodation be considered?
What to do on the spot (besides complaining with a representative, if available) if I believe the carrier airline is refusing "taking care" measures I am already entitled to?
Does the right to care also stand in situations where one is not entitled to a compensation ("extraordinary circumstances", such as strikes or political instability)?
Should a carrier also (after a reasonable delay - say an overnight one) have to provide essential goods needed by specials groups of people (such as baby food or diapers)?
Should infants be entitled to care sooner than adults (both in terms of precedence and delay time before the right kicks in)
I would welcome any answer addressing any of these specific situations, as well as more general guides on what to expect and to properly exercise my rights during these chaotic delays.