I would be really, really, really cautious about relying on that number. Retiring in the mid 40’s means two extra decades of retirement, and spending, and unexpected events. It is also early enough that children(if any) may still have college and weddings ahead of them. The 4% rule does not come with a guarantee, and you might want to have some extra in retirement to actually do stuff with all that free time.
Sorry to be a party pooper. 8-(