#!/bin/bash
s='2020/10/26,249.00,Test10028
2020/10/24,569.00,Test 00074
2020/10/24,1999.00,0016 1708fqb8ba
2020/10/24,1399.00,00450 165058hb1bda
2020/10/23,399.00,Att-10170 158bb8ba
2020/10/22,599.00,Ref:10150 1605fk0bsf
2020/10/22,5669.00,1605fk0bsf'
rx='([^0-9]|^)([01][0-9]{3,4})([^[:alnum:],][^,]*)?$'
awk -v r=$rx 'BEGIN{FS=OFS=","} {print ($3 ~ r) ? $0 OFS gensub(r, "\\1\\2\\3,\\2", 1, $3) : $0 OFS}' <<< "$s"
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
2020/10/26,249.00,Test10028,Test10028,10028
2020/10/24,569.00,Test 00074,Test 00074,00074
2020/10/24,1999.00,0016 1708fqb8ba,0016 1708fqb8ba,0016
2020/10/24,1399.00,00450 165058hb1bda,00450 165058hb1bda,00450
2020/10/23,399.00,Att-10170 158bb8ba,Att-10170 158bb8ba,10170
2020/10/22,599.00,Ref:10150 1605fk0bsf,Ref:10150 1605fk0bsf,10150
2020/10/22,5669.00,1605fk0bsf,