mymonth = 'DEC' 
? INT((AT(mymonth,'JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC')/3)+1)

>mymonth = 'APR' (or any)
>WAIT WINDOW CHRtran(mymonth,'JAN,FEB,MAR,APR,MAY,JUN,JUL,AUG,SEP,OCT,NOV,DEC','01,02,03,04,05,06,07,08,09,10,11,12')
>