In-mid 2015, China started the build-up of the third generation BeiDou system (BDS-3) in the global coverage constellation. The first BDS-3 satellite was launched 30 September 2015. As of March 2016, 4 BDS-3 in-orbit validation satellites have been launched.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): When was the first BDS-3 satellite launched?
30 September 2015