Four hours or eight, and the deciding factor isn't the school or the course tier, it's the county your case sits in. Wake and Guilford counties mandate a 4-hour course; every other North Carolina county requires 8. No other state in our coverage splits course length by geography this way, and it's the single most common way North Carolina drivers waste money on this: a Raleigh driver buying the 8-hour course they didn't need, or a Charlotte driver buying the 4-hour course that doesn't count.
So the sequence is fixed: establish which version your situation requires, from the court that's handling your ticket or the DMV if you're on its point-reduction path, then buy exactly that version. Providers sell both, at different prices, $27.95 to $59 in our latest pull, and a checkout page won't stop you from choosing wrong.
The hours themselves behave like everywhere else online: progress saves, sittings are yours, and the deadline belongs to whoever required the course.
And standing behind the whole question, as always in North Carolina: for most first tickets the courtroom PJC outperforms any course of any length, covered on our points page. Courses we track are compared on the North Carolina page.