+1 878(my-number) will be a second line for the cellular phone. If I had the tens of thousands of dollars to acquire all of my numbers, I will likely have a business. The 878 number can be used a business number. Another option will be to provide a second telephone number to people that I don’t want to have the 412 number. Since my phone is dual SIM, I am able to carry one phone for both SIMs therefore making things more efficient.
As with the SIM-1 line, this line will support unlimited voice, and SMS capabilities. Data will not be necessary, and the phone will use SIM-1’s data capabilities, and this will include RCS, and iMessage messages sent to/from SIM-2.