Show more of your code? Where is $change ever set true? What is $false?

Also, try:

$plat = "asdfb\tssf";
use Data::Dumper;
$Data::Dumper::Useqq=1;
$Data::Dumper::Terse=1;
print "Platform: ", Dumper($plat), "\n";
[download]

to see what's in $plat in a more definitive way.