True, but what has been accomplished with the Linux Sunxi community is a shortening of that loop to bring up new boards with modern kernels, the Pine A64 for example took only a year to gain support[1], and that was around the time they actually started shipping in quantity. Additionally, many of the ethernet drivers, HDMI PHY drivers, Cedrus (provides H.264 & H.265 decoding @ 10bit) are reusable on new chips like the H5[2].

I would not expect much from Allwinner directly, but at this point there is a sizable ecosystem and mainline support for most of their chips, which can't be said for most other ARM vendors. Another aspect of this is Allwinner sells most of their chips thru multiple business units, with the silicon being exactly the same, just what is silkscreened on the top of the package being different[3].

1 - http://www.cnx-software.com/2015/11/10/allwinner-a64-datashe... and https://forum.armbian.com/index.php/topic/1917-armbian-runni... 2 - http://www.cnx-software.com/2016/08/17/allwinner-h5-is-a-qua...

3 - https://forum.armbian.com/index.php/topic/2099-crypto-engine...