Code:
awk -F, '
BEGIN {CNT+=2
}
NR == FNR {a[NR] = $0
b[NR] = $1
next
}
$1 >= b[CNT] {CNT++
}
$1 < b[CNT] {print a[CNT-1]
print $0, RS
}
' file1 file2
20160525162519,SN1
20160525162522,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162519,SN1
20160525162523,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162524,SN2
20160525162524,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162524,SN2
20160525162525,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162524,SN2
20160525162526,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162524,SN2
20160525162527,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162524,SN2
20160525162528,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162529,SN3
20160525162529,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162529,SN3
20160525162530,464374526,1464193527,206,0,0,0,0,1,1,544,544
20160525162529,SN3
20160525162531,464374526,1464193527,206,0,0,0,0,1,1,544,544