Start date on I-94 and grace period to join New company


My husband filed L1b to H1b on 11th May with COS and it got approved on 28th in USCIS site. We recieved approval notice today(5th OCT) with I-94 , start Date as 1st of OCT.I filed my L2 to H4 visa(COS) independently, which is still in “initial review” with USCIS.Currently I am working on L2 EAD. I have few questions on the same.

1.When we spoke to attorney regarding quitting on L1 and L2 EAD , we are asked to quit our jobs immediately which is not realistic as we have to serve atleast 2 weeks notice period.Is there any grace period to move to H1 and H4 as we recieved the approval notice today in PDF format from our attorney, still not recieved a hard copy of the same?In some blogs I have seen, they say USCIS considers 2/3 weeks of grace period.

2.As my H4 is not approved yet, what is my status now?If someone(non-profit organization) agrees to sponsor my H1b in cap-exempt, can they do it before any decision made on my current H4 petition, or we need to wait till the decision being made?

Appreciate your help on this.