Well the last paragraph says it all.
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Note - Due to a changes in the black dyes used on our pre-dyed BLACK clothing items, Discharge Paste sporadically works on these items. Test, test, test! At this point, the only thing working consistently on our pre-dyed black Rayon and Cotton clothing is pure bleach. | |  | |  | |
Test, Test, Test!
Get 2 or 3 extra black T's and run some tests. Give them a wash and keep track of your findings for possible future use. Good luck