Probably Jan. Again, it would depend on the operational needs and actions of the Squadron concerned. Here's a typical example scenario.
The Squadron carried out an Op on Dortmund on Monday night, the last aircraft returning to its Lincolnshire base at 05.00 hours.
The crew went through de-brief, had breakfast, and went to bed.
Meanwhile, the aircraft are fully checked over, cleaned out, and any problems, damage etc noted and logged in the Form 700.
A Warning Order is received at 10.00 hrs, preparing the squadron for operations again that night, this time to Stuttgart.
The ground crews are busily servicing the aircraft which, at the least, will possibly mean cleaning the spark plugs, all 96 per Lancaster. Meanwhile, the target area is being studied by the Operations Officer and Intelligence Officer, and the briefing maps being prepared. The Squadron's role is to be area bombing of an industrial complex, using H.E. mc bombs, and the range to the I.P, is 600 miles. This allows the amount of fuel required to be calculated, and the weight and distribution of the bomb load to be worked out.
Time over target is notified, which indicates a required take off time of 21.30 hrs. As it is now 11.00 hrs, that leaves ten hours before the crews are due out to their aircraft, 12 of which are required for the operation, and these are dispersed around a one and a half mile perimeter dispersal area.
The fuel store is 3/4 of a mile from the dispersal, on the south side of the field, and the bomb dump is one mile from the dispersals, on the north east edge of the field.
Briefing has been set for 19.45 hours.
That leaves a total eight hours, forty five minutes, before the crews arrrive for briefing. At the briefing, the target will be disclosed, the routes to and from indicated, altitudes for approach and bombing disclosed, together with such details as markers, nav aids, expected enemy flak and nighfighter reaources etc etc, The Radio ops and Navigators will attend a separate, extra briefing, in order to gather specialist information allied to their 'trades'.
Meanwhile, out on the dispersals, the ground crews have been carrying out any remedial work neccessary, which will result in some aircraft at least needing a flight test, and some might require extra attention, such as compass re-calibration. This means that the aircraft wiil need to be moved to a compass swinging platform or, made ready for flight.
At this time, the crews are just about rising from their beds, and it is now 13.00 hrs.
With engine running checks completed, all maintenance and / or repair work coming to an end, the first aircraft are ready for a 30 minute test flight, at which time it is probable that all of the radio equipment in each aircraft will also be tested.
With all aircraft now ready for preparation for the nights' operation, it is now around 14.30 hours.
The fuel store has received the orders to load xxx thousand gallons of fuel onto the available bowsers, which will take approximately one hour. Meanwhile, the bomb dump has received similar orders, with the neccessary 'paper work', clearing the release of xxx thousands of pounds of HE bombs, in 500 pound and 1,000 pound mc units. The two fuses for each bomb are taken from the racking in the separate fusing sheds, and packed into steel containers, which are then loaded ont trucks to be driven to the dispersals, whilst the hard work of getting the bombs onto the trolley 'trains' commences.
As the flight distance will be around 1,300 miles in total, the fuel requirements, including reserves, are approaching maximum load. Each aircraft will take possibly around 20 to thirty minutes to fuel-up, check and secure. This has now got underway, with the bowsers running out to the dispersals and, if required, returning to the fuel store to re-load and attend another Lancaster.
The bomb-trains are now snaking around the three miles of perimeter track, with the required number of trolleys being delivered to each dispersal.
Each fully laden trolley can weigh uround two tons, and these now have to be man-handled into a precise position, under the open bomb bay of each Lancaster. There might be three or four per aircraft. With the bomb trolleys in place, each bomb is then prepared, being fitted with its tail-fins, and nose and tail fuses etc, before being hand-winched into the bay, where it is then attached to the bomb-carrier shackles, and the fusing wires attached, before the release clamps are locked, and the safety pins checked.
With this work complete, the ground crews have time for a much-needed break, and a mug of tea and a 'wad' (sandwich), as it is now around 18.00 hours, and the aircrews might be sitting down to a quick meal before going to briefing.
Apart from the taxiing and take off rosters being sorted, now all is ready for the night's operation.
Maybe not a fully accurate description of how it happened, but it'll probably give you an idea I hope!