(1) If a living will entered into before October 1, 2013, was valid at the time of execution, it remains valid.
(2) A living will entered into on or after October 1, 2013, that evidences an intent that it is entered into under this subchapter is valid.
(3) A living will entered into on or after October 1, 2013, that does not evidence an intent that it is entered into under this subchapter may be given effect as an individual instruction if it complies with this subchapter.