when did patient 97330 first had the maximum value of sodium since 03/2102?
select labevents.charttime from labevents where labevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 97330 ) and labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = 'sodium' ) and strftime('%y-%m',labevents.charttime) >= '2102-03' order by labevents.valuenum desc, labevents.charttime asc limit 1