I do not see any clear posts on this so can someone please help us out?

Question: I have a jailbroken 1.1.1 on ATT.

Do I simply upgrade from my jailbroken 1.1.1 to 1.1.4 VIA ITunes and then use iLiberty+ to jailbreak?....or do I need to factory reset first or restore to 1.1.4? If I do this option will I lose all my contacts, etc.. (downside?)

Thanks Much!