cuDNN: NHWC format not supported unless manually specified?

I noticed that calling cudnnSetTensor4dDescriptor with the CUDNN_TENSOR_NHWC format returns 9 (“not supported”). However,

int ns = c*w*h;
int cs = 1;
int hs = c*w;
int ws = c;

status = cudnnSetTensor4dDescriptorEx(d, dataType, n, c, h, w, ns, cs, hs, ws);

which should be equivalent, returns “success”. Why the discrepancy, and is the NHWC format supported at all?

if you try to use this tensor to do a convolution, the convolution routine will return that it is not supported as well.
WE plan to support this format in the next release

Cannot you tell, when is planned the next release?

The support of OpenCV-formatted (NHWC) images may be critically important.

Bumping this topic up, because I am currently having the problem that my data is in NHWC and according to the preliminary documentation of v3 (next version) says that NHWC will not be supported for backprop.

May I also ask: Is there any library function that I can use to convert between NHWC and NCHW on the GPU? Many thanks in advance.