DISCNUMBER vs. DISC

Hi,

I want to keep track of the cds I ripped by providing a unique id in the flac metadata referencing the cd. I mark the cds with a glue label with consecutive numbers.

Now I discovered that I inconsistently used the tags DISCNUMBER and DISC for this. In fact a tagging program I used before used DISCNUMBER and with beet I used DISC.

If I am correct DISC is not an official tag so my hope is that beet will never overwrite this tag with a value from MB. Is that correct?

What shall I do now?

Can I bulk copy the value of DISCNUMBER to DISC with a beet command?

TIA
juh

Note that DISCNUMBER in Vorbis comments (which is what FLAC uses) has a specific meaning and may be set to 1 (out of a total (DISCTOTAL/TOTALDISCS) of 1) for many releases.