My understanding is that the date stamped is the SCHEDULED finish date. Actual finish date might be earlier (pretty unlikely) or a few days later due to problems, parts shortage, weather delays or other acts of God. I don't think that specific days of the week matter, maybe starting on a Tuesday and finish on a Thursday would be best case. But even if you could schedule it that way, reality will be different much of the time.
There might be good and bad times of the year for a build. Spring time in a good economy and the factories might be building in excess of capacity. Cold, wet winter weather can cause problems as individual components are not equalized before assembly. In my opinion, late fall would be the best time, slower build rates, decent weather and mid-year model improvements ahead of the Louisville manufacturers show.
Texas Baptist Men-Retiree Builders member since '01
13 Silverado 3500HD D/A, 2wd CCSB srw, custom RKI bed
11 Cruiser CF32MK