I wonder, what should I do if the bandcamp release date is incorrect. One of the albums an unsubmitted band said in the FB page that their debut album will be released on Nov 2010, but the release date of the digital Bandcamp version is in Jan 2010, before the actual release date. How often do this occur?

Well, some Bandcamp re-releases, especially of older releases, often may have the original release dates. It happens. It always isn't possible to determine exact release dates for them. In this particular case, what is the context? Seems like the information about the actual release date might be available.

Also, are you sure Nov 2010 doesn't refer to another release/version, for example a physical one? How did you come to this conclusion?

I contacted the band members

Did it say January 1st, 2010? If so, that is what it defaults to when the uploader fails to choose an exact release date (Bandcamp requires this). Chances are it was just guessed and/or not entered correctly, and November is probably correct.

It has changed however

Is this how you came to that conclusion? Or what are you replying to?

You aren't being very clear about the matter, so it's pretty hard to say anything very useful.

Because an incorrect release date could be counted as an invalid album.

Well yes, it would. You are still being too vague for us to help much.

what's the proper way of dating a later digital release on bandcamp?

What do you mean by "later?"

like a band putting their 1998 album on bandcamp now.

That's BS for a digital release, so put "Unknown"

Sometimes there might be announcements or something regarding these digital releases, so searching might help. Or asking.

well, most bands simply sign over the digital rights, there's not much fanfare surrounding digital re-releases... itunes usually has the correct date for the digital release, but bandcamp, google play, etc... forget about it

how do i put "unknown" as the date? last I tried, it wouldn't let me save the version without at least a year.

Well, if its a child entry just clear all of the date fields and it sets it to unknown. You can't do this for parent entries, so you have to do some research to at least narrow it down to a year. Thankfully Bandcamp has only been around since 2007, and only truly prevalent for the last 3 years or so. Not that difficult, but otherwise it can't be added as a standalone release. (for now....)

thanks