At mandie, i was lucky to have done my FSW from London, it took less than a year to get my visa 9months to be precise from start to finish, would have been less if i didn't goof during my medicals, told the doc i see patients with TB, they told me to go do sputum test which takes 8weeks. I landed in 2013, my friends that applied at the same time as me only started landing earlier this year they went through AVO.
With regards to your sponsorship application, it might be a good idea to start asap or go the inland route, let your spouse come visit, lol.
My wife and daughter are in the States visiting which makes it easy to go visit, I don't know what I'd do when they return to naija next month.
CADPt