Correct to 20 replicas

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

TestDrive.md

@@ -242,7 +242,7 @@ The `-d` value passes in the argument for your function. This is read via STDIN
 
 Grab OS, CPU and other info via a Node.js container using the `os` module.
 
-If you invoke this method in a while loop or with a load-generator tool then it will auto-scale to 5, 10, 15 and finally 25 replicas due to the load. You will then be able to see the various Docker containers responding with a different Hostname for each request as the work is distributed evenly.
+If you invoke this method in a while loop or with a load-generator tool then it will auto-scale to 5, 10, 15 and finally 20 replicas due to the load. You will then be able to see the various Docker containers responding with a different Hostname for each request as the work is distributed evenly.
 
 Here is a loop that can be used to invoke the function in a loop to trigger auto-scaling.
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