20150603 translate header breaks

(sdc) [09:40 schaffer@itchy sdc] $ gris_translate_header /dat/sdc/gris/20150603/level1_split/
Modifying /dat/sdc/gris/20150603/level1_split/gris_20150603_082644_l1p_004_001_0001.fits:   9%|▊         | 227/2646 [00:37<03:29, 11.54it/s]Traceback (most recent call last):
  File "/home/schaffer/anaconda3/envs/sdc/bin/gris_translate_header", line 7, in <module>
    exec(compile(f.read(), __file__, 'exec'))
  File "/dat/schaffer/projects/kis_tools/bin/gris_translate_header", line 7, in <module>
    run_translate_header(sys.argv[1:])
  File "/dat/schaffer/projects/kis_tools/kis_tools/headers/translate_header.py", line 309, in run_translate_header
    main(f, outfile=f, overwrite=True)
  File "/dat/schaffer/projects/kis_tools/kis_tools/headers/translate_header.py", line 221, in main
    slitpos_cards = wcs_generator.slitpos_cards()
AttributeError: 'NoneType' object has no attribute 'slitpos_cards'
Modifying /dat/sdc/gris/20150603/level1_split/gris_20150603_082644_l1p_004_001_0001.fits:   9%|▊         | 227/2646 [00:37<06:40,  6.04it/s]