Found this chart on a Microsoft restricted site that illustrates which versions you can upgrade to what.
Don’t forget that Home edition is useless in the office, its doesn’t support business networks and cannot join your office network domain. Avoid it at all costs on anything that you intend to use for work.
For home interestingly there is a Family Pack coming to the UK this time that allows you to upgrade up to three computers on the same licence. Makes sense to have the kids legal to.