Management of severe preeclampsia with severe features — antihypertensives, MgSO4, and delivery timing

A 30-year-old primigravida at 33 weeks gestation presents with BP 168/110 mmHg, severe headache, epigastric pain, and 3+ proteinuria. Labs show elevated LFTs and platelets of 89,000. What is the acute antihypertensive of choice (labetalol vs hydralazine vs nifedipine)? What is the MgSO4 dosing protocol for eclampsia prophylaxis? At what gestational age do we deliver despite prematurity in severe preeclampsia?