The daily production numbers were always adjusted to demand, and OE parts availability. One Million units, divided by 260 working days per year is an average of 3800 bicycles per day during the peak production years.
The Bicycles "were built to the dealer orders". The lead time varied between three to four weeks from the time the order was placed with the Regional Sales Company, then forwarded to the Schwinn Chicago factory before they were built. The dealer received an order confirmation postcard, and the actual production date was never more than a day of two off, early, or late. Tom Griffin was the Sales Manager at SSW in the City of Industry, CA. He collected the orders and tried his best to consolidate them into orders going to the geographic same areas if they were not large enough (LTL) for an entire Truck Trailer, or Rail Car shipment. This service was to help dealers reduce and control their shipping costs. Remember that the Schwinn suggested retail prices were only $3.00 per bicycle higher in Zone 3 (west coast).
Jack Smith was the Chicago factory order manager, and he received the orders from Tom Griffin. Jack's job was to schedule the orders and place them in a shipping rotation. His department personnel looked at the orders and counted how many 24" Varsity frames would be needed "three weeks from today" when that particular dealer order rolled down the assembly line. Yes, they had to know how many Sunset Orange, Kool Lemon, Campus Green 24" Varsity frames were needed on the scheduled production day. Scheduling all of this had to be a monumental task, and it was all done with pen and paper, no laptops and app's like we would do today. They had some screw-ups, but overall, it ran VERY SMOOTH all considering.
My families two Schwinn dealerships were located in the desert of Arizona. We ordered "every Chicago built Schwinn" directly from the factory, because they offered us the option of adding Thorn Resistant inner tubes on a "requested basis" to each order. This saved us having to remove the standard inner tubes and replacing them with Thorn Resistant inner tubes. This option saved us labor and parts cost. We almost never bought a "Chicago Built Schwinn" from the Regional Sales Company because the bikes cost us more, the freight from Los Angles to Phoenix was higher than the Rail Car ($2.40 per bike) freight from Chicago to Phoenix. But the main reason was all of the warehouse bikes had standard tubes that needed to be changed over.
Think about it, in order for Schwinn to fill our factory order, AND offer us the option of having Thorn Resistant tubes in every bicycle they would have to have a huge warehouse with the same bicycle, in the same color, in the same frame size, and the only difference would be Thorn Resistant inner tubes. The only way this would be possible would be to build the bicycles "as ordered" and the tubes substituted. I'm sure a few models were exceptions, like Tandems, Tri Bikes, Unicycles, Cycle Trucks, etc. The main "Chicago Built" bicycles that a dealer ordered, 99% of what a dealer actually sold were "built to order". The box "multi part carbon" shipping label was "the first thing printed", well before the first part of the bicycle was assembled. The bicycle began with the shipping label that showed everything about the bicycle. A 120-9 LE, was a 20" frame size, 27" wheel size, Men's frame, in Kool Lemon color ten speed Varsity. If the number was a 220-9 LE it was the same thing but with the optional chrome fenders installed. The assembly line worker looked at the tag going down the assembly line and hung the correct parts on it. The only reason that production date numbers are even close (axle set, or crank stamps) is that the flow of parts at the assembly line was constant. Nothing set for very long before it was attached to a frame going down the line.
If the factory received an order for the regional warehouse, they might build a couple of hundred Yellow 22" framed Varsity's "all in one row". But these bicycles were handled just like the dealer orders, they came off of the assembly line, went directly into a box, set on a dolly, rolled over to a waiting Rail Car, or Truck Trailer for immediate shipment to SSW City of Industry, SSMW Elk Grove, SSS Atlanta, or SSE in New Jersey. As far as the Schwinn factory was concerned, the Regional Sales Companies were just another customer that they shipped bicycles to. If you saw a photo of a regional warehouse order going down the assembly line, it would give you a very different view of how the order/building/shipping system actually worked. I do believe that used a different, small assembly line for exercisers. The last time I saw the assembly line in operation was about 1959, before the exerciser thing got into full swing, so that's my best recollection.
John