Complex sentence: The update also saw a vast increase to the maximum retail storage capacity bring it from 2TB to a massive 6TB when used with three 2TB drives, an option to add a 128GB SSD boot-drive that does not occupy a drive bay was also implemented.
Split into simpler sentences: The update also saw an increase to the maximum retail storage capacity, bringing it from 2TB to 6TB when used with three 2TB drives. An option to add a 128GB SSD boot-drive that does not occupy a drive bay was also implemented.