I have a brick now. 1.1.2 OTB no BB/WIFI/IMEI and BL4.6
so if I upgrade to 1.1.3
first, can I downgrade to 1.1.1?
if I can, then how about oktoprep and then 1.1.2
then how much H/W unlock the downgrade the BL to 3.9?

can some1 tell me why how is that not possible?

You can go to 113 to get back your wifi etc, and then downgrade to 1.1.1, oktoprep and then upgrade to 112. Your iphone will become ipod touch.

But once you upgrade to 113 forget about the h/w unlock by downgrading the bootloader to 3.9. It is not possible until 114 is released.