H1 transfer question

[1human1]

Hi,
I am leaving company A to join Company B. My first 3 year term of H1 is expiring with company A soon in the next 6 months.

1. Do I have to apply just H-1 transfer or (H-1 Transfer + H1 extension) with company B?
2. Is there any number of weeks or period that I can be with out any pay stubs from company A after I leave them before I join company B? Will I fall 'out of status' as soon as the company A stops running pay stubs (they may not revoke immediately as my 3 yr H-1 is expiring with them soon anyway)? I am asking this because the company B may take a couple of weeks to employ me and start paying me.
3. Company B is doing good now. But who knows what will happen in this recession economy?! What are my options to be in legal status if I get laid-off by company B after H-1 transfer with them OR if the H-1 transfer to company B gets rejected for whatever reason?

Thank you for your suggestions.

[1human1]

any suggestions/answers pls? thanks

[yestogc]

PLEASE FILL YOUR PROFILE COMPLETELY.

Now your answers:
1. ................ Yes just H1B xfer, they will extend it upto max of 3 more years.
2. ..................Normally they ask for recent paystubs, but if it is within last 1-2 months it sails through well, w/o triggering RFE. Best option is to do H1b Tranfer under premium processing mode, that way in just few weeks you would know where you stand.
3. ........................ either F1 or H4 or Visitor visa.