Only after the split, ie. with a 1 day delay, I got a short note via email by my broker about the split itself, but no warning about the delay in the data updates following the split (I learned that they update the data 1 day later after the split, ie. there is a gap of 1 day with invalid data (averagePrice=0.0 etc.)). This of course is an unsatisfactory situation for API/program traders. A nigtmare worry for all API users when the API doesn't behave as specified, or gets changed without prior informing the API users.