What concerned Koch most at the time were the frequent changes to the proposed plan of attack. In February the plan was to begin the operation with the Stukas, to be followed by gliders carrying the paratroopers. This did away with the element of surprise and risked heavy casualties in the opening phase of the attack. Therefore on 1 March Koch suggested a change of strategy. Four days later Kesselring, Student, Graf Sponeck, Koch and Witzig assembled to discuss the proposal. From there Koch and Witzig provided Hitler with a report on all details of training regarding the attack on Belgium and Holland. At that meeting Hitler granted Koch’s request and gave him ninety more men from an Army pioneer battalion. This fresh influx (all volunteers from 6. Army who had already served with distinction in the Polish campaign⁸) formed the nucleus of a new assault group under Lt Martin Schächter for the attack on the bridge at Kanne. The first of them arrived at Hildesheim on 11 March.

The recapture of the bridge at Kanne had resurfaced in Hitler’s plans for several reasons: despite the unfavourable terrain for a landing zone, the element of surprise could be used to the advantage of Witzig’s men in nearby Fort Eben Emael. Secondly, Witzig’s men could link up very quickly with the assault group at Kanne, and be used as reinforcements for the men at Veldwezelt and Vroenhoven. However, the new pioneers had little time to prepare for the task assigned to them and this may be the reason why they faced so many problems on the day of the attack. The majority of SA Koch aleady had months of training behind them when the new Kanne group was set up within SA Koch.

From March 1940 efforts were concentrated on creating a detailed description of every target of the attacks. Photographs, Belgian deserters of German stock, spies and even postage stamps were useful sources of information. On 29 February the paratroopers were shown aerial photos of the bridges and Fort Eben Emael for the first time. On 2 March Erwin Ziller, a pilot of the Witzig troop, built a model of Fort Eben Emael. On 23 March Zitter built models of the bridge and surrounding territory at Vroenhoven and the bridge at Kanne. Koch’s men examined all details of their targets, exercised on bridges around Hildesheim and practised placing charges in buildings using shells in mortar cases. Exercises in paddling rubber dinghies were also conducted. By the end of March, training was complete. The men of SA Koch were now welded into a competent and highly efficient fighting force.

All that remained was to perfect the coordination between the ground troops and the fleet of Ju 52s and fighters which would be over the region of the attack from the outset. Other details such as helmet camouflage (after a series of changes the new camouflage scheme for helmets was finally introduced on 23 April)⁹, and practice-handling the new MP 38 machine-pistol became routine for the paratroopers from the end of March. Sniper training had begun on 4 March.

At the end of March the cover names Stahl (Veldwezelt), Beton (Vroenhoven) and Eisen (Kanne) for the three bridges and the two airfields from where the individual attack squads would take off were announced. The choice fell on the Ostheim and Butzweilerhof aerodromes near Cologne, two being necessary because there was no airstrip available from which all Ju 52 tugs and gliders could get up within a window of twenty-five minutes.

Support was extremely important for the setting up and defence of the bridgeheads. Therefore it is understandable that the paratroopers needed artillery cover behind them. On 13 February a company of paratroopers armed with anti-tank weapons was suggested but the idea found no takers. The best solution was for the SA Koch paratroopers to be supported by the Aldinger flak unit which consisted of three batteries each equipped with four 88-mm guns, and another three batteries each equipped with twelve 20-mm guns.