Having reached Release Candidate status, pre-orders are available as of now, and a fresh batch of screenshots shows things are looking sharp indeed.
There is also word of new books in the Battlefront Bookshelf collection that should help improve your readiness:
For more information about all the above and links to previews of said books check out the announcement here.
(...) edited reprints of 1943 tactical pamphlets and contain a treasure trove of information about the tactical employment of commonwealth armour and infantry formations in the field. Seriously, these are better than any How─To guide!
Estimated release date in four to six weeks.