README.md in knapsack_pro-0.11.0 vs README.md in knapsack_pro-0.12.0

@@ -365,9 +365,12 @@
 By default, encryption is disabled because knapsack_pro can use your test files names to prepare better test suite split when the time execution data are not yet collected on KnapsackPro.com server.
 When you will enable test file names encryption then your first test suite split may be less optimal than it could be.
 
 Each test file name is generated with `Digest::SHA2.hexdigest` method and 64 chars salt.
 
+Before you enable test file encryption please ensure you are using fresh API key. You should not use the same API key for encrypted and non encrypted test suite.
+You can generate API key for your test suite in [your dashboard](https://knapsackpro.com).
+
 #### How to enable test file names encryption?
 
 First you need to add environment variable `KNAPSACK_PRO_TEST_FILES_ENCRYPTED=true` to your CI server.
 
 Next step is to generate salt which will be used to encrypt test file names.