OK, so I am a home-based FFL/SOT who is moving to a new home. I have the 5300.38 for my FFL but my questions are with the SOT aspect.

The 5630.7 is straightforward enough, however the instructions state that a 5630.6A is also required. What is the 5630.6A and where in the hell do you find it? Also on the 5630.7, what do you indicate in Section II regarding the tax computation and the “tax due” (11e)? Do I need to pay the 2014 tax again?

Do other FFL's typically submit any of this paperwork prior to closing, or wait until everything is final with the house?

I'm under the idea that any address change is a new application, therefore a new fee.

You are flt wrong about that. If you chage your FFL address your expiration date does not change, nor is there a fee to amend your license.

So just each address needs its own ffl, and a change of address is just a change on your original ffl then?

An FFL only covers one premises.
If you move you fill out ATF Form 5300.38 — Application For An Amended Federal Firearms License.
You cannot conduct firearm transactions at the new address until your updated FFL is in hand.

How long does that usually take? I plan on getting it at home first and then once I find the right spot and feel comfortable making the leap changing to a storefront.

My address change took two months from the time ATF received the 5300.38..............ATF asks for 30 days prior to the move.

Duh...after scouring the net and calling the NFA branch and talking with folks/leaving messages, I finally realized while looking at my 2014 SOT form, the ACTUAL SOT FORM is the 5630.6A.  

I just submitted my change of address this week.
The ex was allowing me to continue transfers at the old place through the spring and summer til she had a contractor lined up for the renovations to the space
Getting my new location through the zoning board, code enforcement and contractors dragged on.There was no way to know when "30 days prior" was going to fall for me.
I opted to simply move stuff in last week and cease operations til I get approved at the new place