Update transition-updated-cr-2017-09.md

Author: svgeesus

css-writing-modes-3/transition-updated-cr-2017-09.md

@@ -93,7 +93,7 @@ The [testsuite](https://test.csswg.org/harness/results/css-writing-modes-3_dev/g
 An [analysis of the test results](https://drafts.csswg.org/css-writing-modes-3/implementation-report.html) is also available
 
 
-:boom:  the tests for features moved to Level 4 are still marked as level 3 tests, so need to be edited to make them Level 4 tests during the CR period
+:boom:  the tests for features moved to Level 4 are still marked as level 3 tests, so need to be edited to make them Level 4 tests during the CR period, once Writing Modes 4 is published. All tests with `srl` or `slr` in the filename are so affected.
 
 ## Patent disclosures