Upgrade Client With Package

Hi,

I planing to upgrade my SEP client from SEP 11 to SEP 12. However I have a few doubts need so clarification.

1) "Distribute upgrade over XX days" If I plan to have this upgrade run over the network over 7 days, do it mean I need to enter 7 inorder for the upgrade to be active within 7 days after I implement the policy?

2) I had a mix environment of Win 7 32bit and 64bits. Do it mean I need to create 2 different upgrade policy for. 1 for 32 bits and 1 for 64 bits?

3) will SEP able to identify the different OS function such as 32 bits and 64 bits?

Hope to hear from you soon.