Interlaced 4:2:2 not implemented

[FranceBB]

When trying to encode interlaced 4:2:2 files with the --tff flag, x262 says that such a thing has not been implemented.
Please introduce 4:2:2 interlaced encoding as this is what professional formats like IMX50 and XDCAM-50 use.

How to reproduce:

x262_64.exe "D:\Temp\AVS Script.avs" --mpeg2 --preset medium --level high --profile 422 --bitrate 50000 --vbv-maxrate 50000 --vbv-bufsize 17825792 --keyint 12 --bframes 2 --no-scenecut --open-gop --deblock -1:-1 --overscan show --colormatrix bt709 --range tv --transfer bt709 --colorprim bt709 --videoformat component --nal-hrd cbr --output-csp i422 --tff --asm 1 --output "\\mibctvan000\Ingest\MEDIA\temp\raw_video.m2v"

to which, x262 replies with:

avs [info]: 1920x1080i 0:0 @ 25/1 fps (cfr)
x262 [error]: interlaced 4:2:2 not implemented
x264 [error]: x264_encoder_open failed