Id3v2.3/v2.4 conformance questions

I have a couple of questions or problems regarding date&time frames in id3 tags.

%RELEASETIME% / TDRL

mp3tag stores the field %RELEASETIME% into a TDRL frame, even in v2.3 tags. This id3 version does not have TDRL frames, thus a TXXX frame should be used instead. TDRL has been introduced with id3v2.4.
? / TIME
The TIME frame of id3v2.3 is not yet supported at all.
%DATE% / TDAT
Although it is supported, the %DATE% field is not properly converted to id3v2.4, imho. As far as i understand the spec the conversion should be TYER+TDAT+TIME <-> TDRC. TDRC is explicitly mentioned in the 2.4 spec as replacement for the deprecated v2.3 frames. mp3tag seems to convert TYER <-> TDRC and TDAT <-> TXXX:TDAT.

-u302320

Could someone address these issues, please?

Release Time is likely that way to be compatible with iTunes; if so, it's unlikely the behavior will be changed. Can't comment on the other 2 issues.

I’m not sure why it would have anything to do with iTunes, since iTunes doesn't make use of tags for either TIME in ID3v2.3 or TDRL in ID3v2.4.

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