I moved out of state BEFORE an IPO on options gained while working in CA that I then purchased as a resident outside of CA. This does not work as others are describing it. CA did and will come after anyone who earned options while in the state.
A VC is investing in a company, like any other stock investment. There is no earned income.
An employee that forward exercises their options pay taxes on date of hire and vest automatically. Post IPO you’re only taxed when you sell.