'XXXX-ax1-d.ett.amrs.bankofamerica.com','UAT','AMRS','AMS','','YYYY','
+ZZZZ',,,,
                                                                      
+     ^ matches here
'XXXX-ax1-d.ett.amrs.bankofamerica.com','UAT','AMRS','AMS','','YYYY','
+ZZZZ',NULL,,,
                                                                      
+           ^ matches here
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The comma after NULL is part of the match and replacement, so the next match starts after it.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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