You entered the TELUS system on April 11 and will be charged from that date up until April 16, as April 17 is your new billing cycle start date. You will see
partial charges
from April 11 to April 16 on your bill. Since you were already invoiced by Vivint up until April 14, you will receive a
billing adjustment
that removes the charge from the April 11 to April 14 period. The partial charges for April 15 and 16 will cover the cost of the two days before the start of your new billing cycle.