This is pink stock, so no minimum time. I have seen many company do the split immediately after getting FINRA approval with no prior warning to shareholders. Not sure about the deadline, but have seen some give 1 or 2 months notice. Doesn't mater anyway now that they have said they will do it, the damage is already done.
Most likely they are just waiting on FINRA approval, then they will do the R/S.
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