I have a problem somewhat related to what happens in this thread.
I have a 35000+ files collection of mixed FLAC, mp3 and ogg files. Most of the mp3 files are ID3v2.4.
After upgrading to v2.57 from a portable older version, I realized that editing some tags resulted in the YEAR tag being deleted from the files. After reviewing the issue, I came to the conclusion that the problem was that some files were not tagged according to the ID3 standard (i.e. with something like YEAR=12-05-1947).
Due to the size of my collection it is not an easy task to locate which files have a non-standard YEAR field. Moreover, sometimes I use it explicitely out of the standard with something like "1927--1932" when the recording date is not available, but the period is.
I had to revert back to v2.52 in order to keep the data in my files, since I don't want to accidentally loose the information. As for this moment, I cannot upgrade to any newer version because that will ceirtanly mean that I'd loose some information along the way.
I fully agree with the need to adhere to standards, but sometimes we need some flexibility for situations that the standards didn't foresee (like not knowing when a recording was released). I think it would be a great improvement if there could be a global option like "Enforce YEAR compatibility" that could be unchecked and prevent mp3tag from deleting the information in my files (i.e. reverting the behaviour to pre v2.53, in which any text could be inserted in the field). At least until I can locate the offending files and correct the situation!
Thanks a lot!
Just a note: my collection is mainly tango and the information of some old recordings is quite often missing. Many orchestras recorded several times the same song and most CD's don't supply recording information. Sometiemes I may know that some recording is the one from 1928 or 1924 but not the one from 1945. If I have to strictly adhere to the standard and use only one date, I miss information, and thus I sometimes solve this situation tagging the files like YEAR=1924--1928 in order to have as many information as possible. At other times the recording date is completely unknown, but it is known that the orchestra only recorded during certain years.