In the past, I’ve repeatedly seen Japanese releases that have “multiple” catalog numbers, usually for limited editions that ship a CD and a DVD. I wondered how to deal with them properly when entering them in MusicBrainz.
In this specific case, I have this release, which currently has the catalog number BVCL-937～938 on MB. I suspect both the CD and DVD have their own number, specifically BVCL-937 and BVCL-938. The official website discography also lists the catalog number as BVCL-937～938. However, on the CD case, this is shortened to BVCL-937～8. And for another release by the group, an editor split the two catalog numbers and entered them separately for the release.
Now, my question is: what’s the preferred style? I’d love to have it consistent across all releases, that’s why I’d like to get some input from the community.
I’d all all catalog numbers separately, as has been done on this release
in your case, it looks like all the catalog numbers are from the same label, but if you’re ever not sure, you can always add a catalog number without a label and vice versa. (though, you might check the labels’ discography and see if there’s other similar catalog numbers first)
I’d add both BVCL-937～938 and BVCL-937～8 too, since they’re technically different, even though they seem to mean the same thing
If you look at the mediums, you should see BVCL-937 and BVCL-938.
Usually we set these two catalogue numbers.
But additionally you can set BVCL-937〜8 as it is printed on the packaging.
Because, why not? 
Thanks, checking the discs was a great idea. I’ll add the individual catalog numbers then! For the combined catalog number, should I use the short one (that’s printed on the packaging) or the long form (that’s listed on, e.g., the website)?
I’d at least do the one printed on the packaging, as that would help identify the release, but I see no issue adding both?