How is your data currently broken up? Your code suggests that everything you showed is one record in @Switch_Array. So you're splitting it on the port-channel lines, which seems ok; you'll get alternating tags and values from that, so you might assign it to a hash. But not if ordering is important.

So you've got a list of elements, each of which is either a port-channel line or a block of data, from which you want to extract the port list.

my @Filter = split /(port-channel \d\n)/, $Info;
for (@Filter) {
    unless (/^port/) {
        # strip out the junk
        s/.*Ports://s; # Everything up to Ports:, even crossing line b
+oundaries
        s/^\s+//m;     # Leading spaces on lines
        s/\s.*//;      # Everything from the first space to the end of
+ a line
    }
    print;
}
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