Oops, something ate the square brackets around the negated character class ^12. Maybe code tags will help, maybe not.

perl -ne 'sub BEGIN {$l="";}$l=$_, next unless /ERROR/;print /^[^12]/ 
+? "$l$_" : $_;$l=$_;' some.log

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Johngg

In reply to Re^4: need to extract top and bottom lines... by johngg
in thread need to extract top and bottom lines... by Anonymous Monk

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