H1b and available

[Aka2016]

First visa approved 3 years on Oct 2013
Employment ended May 2016 Company A
New transfer petition filed company B June 2016 (receipt received, started working)
I94 expired Sept 2016 (3 years first approved in oct 2013), left for India in March 2017
Visa approved May 2017
returned US September 2017
Changed employer October (received receipt, started working)

Questions
How many years left on visa?