Last Action rule : L1b Ext approved after H1B COS approval

My Change of status(COS) from L1B to H1B with Employer X got approved on 20 Nov. My Last date with L1B Employer Y was on 23 Nov. I started working with Employer X from 24 Nov.

Employer Y filed my L1B ext which got approved on Nov 30.

1)What is my current visa status?
2)Am I eligible to work for Employer X on H1B?
3)How soon do I need to go for H1B stamping as it would take for me 2 months(passport renewal + Canada Visitor Visa + H1B stamping appointment in Canada)