Move core block settings across to a new theme

block_remap

# Reset blocks to remove standard placements.

UPDATE block SET status = 0, region = -1 WHERE theme = 'OLD-THEME';

# Pull data across.

UPDATE block AS export_blocks
INNER JOIN block AS import_blocks
  ON import_blocks.module = export_blocks.module
  AND import_blocks.delta = export_blocks.delta

SET
  export_blocks.weight = import_blocks.weight,
  export_blocks.region = REPLACE( REPLACE(import_blocks.region, 'OLD-REGION1', 'NEW-REGION1'), 'OLD-REGION2', 'NEW-REGION2'),
  export_blocks.visibility = import_blocks.visibility,
  export_blocks.pages = import_blocks.pages,
  export_blocks.title = import_blocks.title,
  export_blocks.status = import_blocks.status
 
WHERE export_blocks.theme = 'NEW-THEME'
  AND import_blocks.theme = 'OLD-THEME';