Per the schematic you will notice that the 3.3v output from U3 goes through D1A before it becomes VDD and VDD_nRF. D1A has a forward voltage drop of 0.36 to 0.44V depending on how much load is in the circuit. 3.3 - 0.44 is 2.86V plus or minus the accuracy of your DVM and the nominal offset of U3.
Per the schematic you will notice that the 3.3v output from U3 goes through D1A before it becomes VDD and VDD_nRF. D1A has a forward voltage drop of 0.36 to 0.44V depending on how much load is in the circuit. 3.3 - 0.44 is 2.86V plus or minus the accuracy of your DVM and the nominal offset of U3.
