In terms of time and content, the process of concentration and deployment of the German fascist army against the Soviet Union can be approximately divided into two stages.
The first stage occupied the time from July 1940 to January 1941. It was mainly used for advance of a kind of cover echelon and its deployment on the territory of East Prussia, Poland, Northern Norway and Romania.
During the first stage, the headquarters of Army Group B, 3 headquarters of the field armies (4th, 12th and 18th), the headquarters of the tank group, 12 headquarters of the corps, including 6 tank headquarters, and the so-called "military mission" in Romania were concentrated in the east a total of 44 divisions, including 8 tank divisions.
The second stage, which lasted from February 1941 until the outbreak of the war, was occupied with the concentration and deployment of the main forces near the Soviet borders.
During these four months, the fascist German command carried out the transfer of 113 divisions. They were subdivided into five so-called deployment echelons [Staffel] (see Table 15).
The transfer to the east of a huge mass of people, military equipment, weapons, ammunition was carried out according to a carefully developed plan. From February 1 to May 25, the railways operated on a peacetime schedule, and from May 25, a wartime schedule came into effect. In other words, the transfer of troops accelerated about a month before the war. For the calculated standards of transportation were taken: 70 trains - for one infantry, 100 trains - for one tank division. Due to limited capacity of railroads many mobile units marched to their deployment areas, but their tracked vehicles were stilled transported by rail in order to save their resource. The traffic schedule was so rigid, that the loaded trains, according to the decision of the railway administration, could be sent back if they were not unloaded on time.
1st echelon - 8 divisions total/incl. 1 tank or motorized - 4 February - 12 March - 1 division per 4.5 days
2nd echelon - 18 divisions - 16 March - 8 April - 1 division per 1.5 days
3rd echelon - 16 divisions - 10 April - 10 May - 1 division per 2 days
4th echelon- 47 divisions total/incl. 28 tank or motorized - 25 May - 22 June - 1.5-2 divisions per day
5ht echelon (strategic reserves) - 24 divisions total/incl. 3 tank or motorized - after 22 June
total 113/31 divisions
It was envisaged that all military supplies were placed in the staging areas for the offensive as close as possible to the border, while the troops were unloaded and concentrated at a relatively large distance from the border. At the same time, the closer the time of the attack approached, the closer to the border the unloading stations were assigned. Whereas the first deployment echelon was unloaded at stations located on the Danzig, Katowice line, 150-180 km from the border, then the second - already at stations located on the Königsberg, Warsaw, Thorn line, 80-100 km from the border, and the third - at stations located on the Allenstein, Radom line, 60-80 km from the border. The fourth deployment echelon was also unloaded on approximately the same line.
Movement of troops to the initial areas, which were 7-30 km away for infantry divisions, and 20-30 km from the border for armored and motorized divisions, was carried out secretly, using night marches during the first half of June.
The advance of the fourth echelon to the designated areas, which completed the concentration of the main forces for the first strike, was the most crucial stage of the strategic  deployment. The so-called maximum movement schedule came into effect. In fact, this was already an open concentration of the main forces at the borders of the USSR, which could be somehow explained, by resorting to all sorts of lies, but no longer hidden.
The transfer of troops of the fourth deployment echelon was carried out in two streams. The troops of stream "A", moving from May 12 to June 9, included a number of infantry and motorized formations, all ground units and subdivisions of the air force, rear services of the ground forces and units of the GHQ. The advance of the troops of stream "B", which took place from June 2 to the beginning of the war, coincided in time with the covert combat deployment of the previously trasnferred formations. At about the same time, the designated areas were occupied by tank and not yet deployed motorized formations.
The covert advance of strike groups to the starting areas for the offensive completed the strategic deployment. It was assigned only the last few days before the invasion, and it was planned in such a way that these groups would approach the border line on the night before the offensive and stay here for only a few hours. In approximately the same way, the German-fascist strike groups were deployed to attack France.
Movement pf infantry formations to the initial areas for the offensive was undertaken 12 days before the start of the war, and tank and motorized formations - 4 days. Infantry divisions followed to the border using night marches, under the cover of reinforced battalions stationed there in advance.
The fascist German aviation also pulled closer to the border. Back in the spring of 1941, fighter and close recon aviation occupied airfields at a distance of 40 km, and bomber aviation no further than 180 km from the border. The concentration of most of the flying units at the airfields ended by 18 June. Some air units arrived on the eve of the day of the offensive.
The advance and deployment of headquarters was carried out the last, as was already practiced in the German fascist army on the eve of the invasion of Poland and France. Before the attack on the USSR, the headquarters of the operational formations that occupied the designated deployment points were disguised as departments of the military command and control bodies, which had been here for a long time and whose location was not a secret for Soviet intelligence. The movement of these headquarters to the deployment areas of subordinate formations took place on the eve of the invasion, starting from the moment tank forces arrived at their places.
Thus, the Hitler's command attached great importance to the final stages of strategic concentration and especially the deployment of troops. At these stages, the initial attack groupings of the German fascist armies were created, the troops were brought to full combat readiness.
The last, fifth echelon of the deployment, which consisted of strategic reserves (24 divisions), moved forward and was put into battle during the outbreak of the war.
Including these strategic reserves, from the beginning of February to July 4, 1941, 61 infantry and 29 tank and motorized divisions, a large number of GHQ units, ground units and air force units, rear units and agencies and other special units were moved to the borders of the Soviet Union between the Baltic and the Carpathians. To transport these troops, 11,784 echelons (200,000 rail cars) were required.
The planned schedule for transportation of echelons 1-5 (Staffel 1-5) is available, for example, in the documents of the Army Group South (NARA T311, R260, frame 000205 and then).