1. I'm going to use the power of LTSpice to answer that. I isolated only the bias part of the circuit, and asked it to show all of the DC voltages and Currents (with no input signal). Note I(R1), I(R2), and Ib(Q1).
2. It is not the input capacitance of the resistors that matter, even though at ~100MHz they do exhibit some between their two ends. It is primarily the base to emitter and base to collector internal capacitance that shifts the resonant frequency. My little 3pF accounts for about half of the delta from 87 to 58 MHz. The rest is due to the transistor. When you build the circuit, the shift will be even worse, due to the stray capacitances of the wires, pcb traces, the bias resistors, the capacitor bodies, the coil turn-to-turn capacitance, etc. Hint, when you build it, you will need to reduce C1.