Both L1 and H1 are approved

I am currently working for CompA on L1 valid till Sep-30-2017.
CompB filed my H1B(Change of Status) got Approved on Aug-29-2017 with I-94 valid from Oct-01-2017 to Sep-12-2020.
Also CompA filed L1 Extn. got approved on Sep-15-2017 valid from Sep-12-2017 to Apr-19-2019.
Will my H1 override my L1 or vice versa ? Appreciate your response .

Since the start date of your H1 is greater than L1, I believe your H1 might override your L1 until you decide to go with L1 only and update to go with that. Please make sure to take a decision as earliest.