I can think of a solution.
You can update the new depreciation GL account in AO90 in the first place in order to prevent wrong postings.
Then, since these depreciation accounts are not automatically posted, you can post a transfer entry from old GL to new GL through FB01.
Else, post entry by entry for all 12 months postings to new GL through FB01 by inputting a right narration in text field.
Hope this helps