L1 to H1 COS

[xplosion79]

I applied for L1 to H1 COS in June 2012.

Earlier I assumed that I will get the result before Oct 01 (Acceptance or denial) but things are getting tricky now.

I have few questions if some one expert can please help:

1. If my H1 gets approved after Oct 01 (Say Oct 20), when will it be effective from?

2. Will I be on L1 till Oct 19 and immediately on H1 on Oct 20? My employer said we get some buffer time 2 weeks or so but I haven't heard of anything as such anywhere.

3. I know that once the H1 is approved, the L1 automatically gets invalid (Since this is Change of Status).

If it is approved on Oct 20 and unknowingly, I work for my old employer on Oct 21 on my L1B visa, will this be breach of visa norms?

Please reply to my queries.

Thanks in advance.