Consider the following distribution network. The first process, Process A, is unloading cargo from ships in California ports. Lets assume that this activity has a rate of 57,000 units per day. The next step, Process B, is to load trailers for the shipment to the DC (distribution center), assuming a rate of 60,000 units per day. The goods are then processed at the DC, Process C, which involves sorting and packing at a rate of 44,000 units per day. Lastly, there is Process D, which involves shipping trailers of goods to customers at a rate of 31,000 units per day. This system is working 24 hours per day.

As part of restructuring the distribution network, a third-party logistics (3PL) is hired to take the loaded trailers from Process B and deliver them to customers. Given that the maximum delivery capacity of this 3PL is 28,000 units per day, what is the total output of the restructured distribution network? Identify the bottleneck(s) of this system.