You can use MC's expression language to pull / parse pieces from your album tag.
You'll want to do this in 3 stages: first, grab the label field, then the year field, and finally you can redefine the album field.
To grab the label, you can use the expression:
=listitem(listitem([album],1, /(),0,/, )
To grab the year, use the expression:
=removeright(right([album],5),1)
And finally, to pull out the album portion of your existing album tag, use:
=listitem([album],0, /()
Select the files for which you want to change tags.
Go to the Comment field in the action window, select it to edit, and enter the first expression above. Copy and paste exactly as it is from the = to the final paren. When you hit Enter, you should see the value you desire.
Next, go to the Year field in the action window, and do likewise using the second expression.
Finally, you can now change the album field, removing the stuff you've moved to other fields. Use the third expression to do this.
Try this on one or two files to ensure it works as you expect.
Edit: it is not clear to me if you actually have square brackets around your album and label; if so, reply and I'll update the expressions to accommodate.
Edit: fixed the third expression which grabbed the second list item rather than the first.