24.7.2  Any anti -doping rule violat ion case which is pending as of the Effective Date and any anti -doping rule violation case brought after the Effective Date based on an anti-doping rule violation which occurred prior to the Effective Date, shall be governed by the substantive anti -doping rules in effect at the time the alleged anti -doping rule violation occurred, and not by the substantive anti -doping rules set out in these Anti -Doping Rules, unless the panel hearing the case determines the principle of “ lex mitior ” appropriately applies u nder the circumstances of the case.