By now, filming is performed in 99% of cases digitally, with highly efficient file formats both in terms of space occupied on disk and quality, with storage systems compatible with any computer, and standardized data exchange interfaces.
The "offline-online" concept has become completely obsolete as the files uploaded at the beginning of the processing can be used on the same machine to make the final movie, and the same workstation, now at a very low cost, can be used for every single step of processing.
The loading of the material into the machine is almost instantaneous, in some cases not even necessary, as the workings can be carried out virtually on the same HDD in which the filming is transferred. Often these are just reasons of opportunity and security that make it necessary to transfer data to local workstation storage or to a SAN. The transfer times are in any case extremely reduced, of the order of a few minutes for hours of shooting, and can often be carried out during the processing itself.
The cost of storage also decreases exponentially over time, and the increase in the efficiency of compression formats with the same definition and quality makes the quantification of load times and machine space necessary for processing almost obsolete.
These upload times are final: once imported, the videos do not have to be uploaded again for a higher quality version of the work.
The workings are extremely speeded up, the rendering times virtually canceled, and the color grading can be carried out in a technically flawless way on the stressed machine on which all the other parts of the work are carried out. When material loading is not physically possible on a single machine, current network technologies allow fast enough access to remote files to make copying from one machine to another unnecessary.
This is even when there is no centralized storage, a common possibility.
In summary: the loading time of the material is almost zero, the space occupied on the storage is reduced, there are no need for file passage, the workstations are cheap and are interchangeable and multifunctional, the files used in processing are the same used for shooting, and often also for delivery, the sws are efficient and allow you to use a single environment to perform common processes.
Despite this, on the price lists still reads a separation between offline and online, and an hourly definition of the costs of making the final movie.
This is totally useless for some types of work.