Information on how the Germans were marrying up bombers and their escorts was derived from a series of messages from Octeville which were intercepted during August, before and after »Adlertag« (Cherbourg-Octeville was III./JG 2’s base at the time). KG 55 was told on the 7th to detach a crew there to drop smoke bombs as a navigational aid for JG 2. Five days after that, an unidentified fighter Gruppe requested the immediate supply of 100 smoke bombs for an operation and Bletchley Park associated this with a message from Octeville at 0630 that morning, asking for four incendiary bomb »Schächte« (shafts or trays) for two operations by He 111s. More was learned when, on the evening fo the 14th, the same airfield asked for "150 »Wassernebelbomben« (literally “water smoke bombs”, probably similar to the RAF's smoke floats) for marking out line of flight in both directions France–England. Very urgent”. The British analysts’ interpretation was that the bombs might be needed to indicate to fighters the course of the bombers they were escorting, obviating the need for rendezvous over coastal airfields where Chain Home radars could spot the formations assembling. The plans for a series of raids 10 days later included 4.(F)/14 dispatching two Do 17 to lay smoke lanes (»Nebelstraßen«) in the Channel to Cherbourg-Maupertus, taking their orders from Jafü 3. On 12 September it was learned that »Dauerrauchpeilbojen« (persistent smoke floats for taking bearings) were available to units in Belgium; dropped from 100 metres, they gave off white smoke for 90 minutes.

A wireless station was ordered on the 15th to pack up and move at once to Guernsey aerodrome where it was to contact Stab JG 53 and stay permanently manned. In addition, the island’s flying control was to relay the take-off and landing times of KG 76 aircraft to the Geschwader HQ at Dinard. The same day, Dreux was told to supply 20,000 litres of aviation fuel and corresponding supplies of oil for stocking-up of Jersey. On 17 August signals Junkers captained by Leutnants Denker and Brettner were on Guernsey and Jersey respectively, working with ZG 2; at midday on the 18th, a Ltn. Damm landed his signals aircraft on Jersey, taking over support for ZG 76. »Trupp Schilling« reported on 4 September that it was acting as the advanced wireless station for JG 53 but since Guernsey served as a jumping-off airfield, the Geschwader could only be reached there at certain times. Next day, Schilling (possibly an Unteroffizier) asked 1./LN Regt. 34 to hand over documentation about a vehicle to JG 53 in Dinan “during operations in Guernsey”.

Ob. West’s move to Trouville was revealed by ULTRA on 18 August, although his two Junkers W.34 were parked at Sangatte (over 200 km away) and were permitted to fill their tanks at any airfield. There was a flap next day as Fliegerkorps V tried to find what had become of a package intended for KG 51. Amongst other documents this had contained a guide to types of ship, a manual of sea warfare and a gazetteer of small harbours in South and South East England. If these items could be read as signs of the build-up to an invasion, perhaps a decrypt on the 19th suggested how they imagined carrying it out:

… in a radius of 5 km from London. Parachute troops are to descend near point SR. Heaviest artillery on the coast Calais–Dunkirk. Time of opening fire 1849 Central European Time.

Since this was not read until about 36 hours after it was sent (at 1326 on 17 August) and none of these things had actually happened in the interim, the signal may have been part of a German exercise.

A more credible signal, at 1100 on 22 August, ordered 14 Ju 87s to attack a convoy off Deal in 75 minutes’ time and a follow-up at 1135 called for support of a “heavy attack” on a convoy off Dover. It is unlikely that this was read before it became apparent that the only attacks on convoy CE9 had been by long-range guns and the Bf 110s of Erprobungsgruppe 210.

Deciphered traffic, particularly from a control centre at Boulogne, gave extensive information on the deployment of sea rescue boats and planes. Like almost everything else, these signals were read in arrears but did show what deployments to watch for as a precursor to operations and where the regular waiting positions were (a clue to the routes raiders might take). At its most basic, the boats were often told whether or not they should expect any operations on a given day. The 24th of August demonstrates the variety of information that could be derived:

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