Upon the effective date of designation of a State under paragraph 5(c) of the Act, no poultry products can be processed within the State unless they are prepared under inspection pursuant to the regulations or are exempted from the requirement of inspection under §381.10, and no unexempted poultry products which were processed without any inspection can lawfully be distributed within the State. For a period of 90 days from the effective date of such designation, poultry products which were processed in any State listed in §381.187 and inspected and passed under the supervision of a responsible State or local inspection agency or exempted from State inspection can be distributed solely within the State, provided they are not adulterated or misbranded, except that the official inspection legend shall not be used. Such products may not enter official establishments. After said 90-day period, only federally inspected and passed products may be distributed within the designated State, except as provided in §381.10.