What does an airline pilot do?
An airline pilot flies an aircraft and is responsible for the safe conduct of a flight. Work starts with a briefing and preflight checks and ends with a debriefing. The long training of airline pilots is not mainly for the day-to-day work, but for the rare moments when something goes wrong. The time as a co-pilot is also training, namely towards captain.
Up-to-date ATPL knowledge helps in an airline pilot's daily work, for example in performance calculations, weather analysis and emergency procedures. Cockpit procedures have a purpose that must be understood, not just known; an airline pilot must also be able to land with an engine inoperative, with flap problems and in bad weather, and decide when diverting is safer. Under EU-OPS, the flight duty period starts when the airline requires the pilot to report for duty and ends at on-chocks after the last sector. The larger an airliner, the more slowly it responds because of inertia, which requires thinking further ahead.
Pay For Time (PFT) and Pay to Fly (PTF) mean the same thing: you pay an airline to be allowed to fly for it as a pilot and so build experience. For airliners, broadly speaking, the VMO limit depends on pressure and the MMO limit on temperature. The approach ban (JAR-OPS) means you may always start an approach, even if the RVR is below minima, but at the outer marker or equivalent position the minimum RVR must be available, otherwise you discontinue the approach.