Changing Job using I-140 approval in the 7th year of H1B.

[LaborSeekar]

I want to change job using I-140 approval. I'm on the 7th year of H1B.
What I learned from the forum is

Ask the new employer to get the H1B transfer/extension by using premium process and then change job. (You will get 3 year extension and good until another extension is needed and by which time I should have my labor/I-140 approved with the new company)

I'm sure that My H1B Company will cancel H1B/I-140 if I leave the company.

My Q is

1. Is the above job change statement based on the assumption that the employer shouldn't cancel the I-140.
2. Will I be out of status if My H1B Company cancels I-140 after I change my job to the new company?
3. I understand that once I get the H1B transfer/extension from the new company, there is little chance that INS may know about my status until I apply for another extension.

But the important Q I want to know
Is there any law (or something in the book) that says it’s ok to continue on 7th year H1B while the new company is in the process of obtaining Labor/I-140 approvals?
(Because my new company lawyer strictly want to see this. This is what stopping my new company to hire me.) They say I will be out of status if my company cancels I140 even though I have a new extension on H1B visa and so the immi lawyer of the new company don't want to do it even my manager want him to do it)

Is taht true? If not can you point me to the link, I want the shut that buggers mouth.
Thanks