To date, SUNXI has made a page for the Banana Pi M2Ultra , but not much else. Apparently they invite English writers will complete the documents.
No listing for the V40, only R40.. The SUNXI support is currently one page, not fully integrated with other wikis and searches at their site.
The listing of Allwinner devices currently omits mention o the V40.
At this time, BPI seems ahead of Sunxi in support