Everybody has "an order of things".  For example: The 1st two things my wife does in the morning. 1) Slap the alarm clock and 2) Slap me up side the head.
The list goes on, but, that's just a short example and doesn't "really" relate to anything on ebay.
What I wanted to relate, here, was "my" order of things that relate to you as a buyer & me as a seller on ebay. Mainly, the shipping of your stuff.
So, here goes.
Lets assume you won an auction and wonder when it will ship?
ASAP is my answer. The quicker I get your parts headed your way, the better for both of us.  BUT, What does ASAP mean coming from me? 
That's where the "order of things" in my world come into play.

1) LAKE...Sorry, I tournament fish and the only way get better is TIME on the water.  (it's my weak spot and if I'm not working, I'm at the lake).  I'll ship your parts as soon as I get to work.
2) Buy it Now listings get priority.
3) My ended auctions are sorted in alphabetical order by "your user ID".  So, If you ebay user ID is "Applejack", It's going to one of the 1st invoices I make...and packaged sooner than ebay user ID "Wheresmystuff".
4) Gravy...The guys in the shipping dept call little fist sized items "gravy". Those items are easy to package and they can box 50 of those in the same amount of time that it takes to build a package around a receiver hitch.  Gravy gets priority. 
5) BIG ODD shaped Stuff (like a receiver hitch).  Takes awhile to package, real pain in the hiney, BUT, has to be done and will get done...just gotta get rid of all the "gravy" 1st.
6) Multiple orders.  I've sorted through your 8 to 50 items and reduced your shipping cost "hopefully" a bunch.  The shipping dept sees this pile of parts and asks if there are any more Receiver Hitches that need boxed, Please???    These go last and seem to take f-o-r-e-v-e-r to package in such a way as for nothing to get damaged, and, to tripple check to be sure nothing gets left out.   If the shipping dept guys love their job, they would love "multi-orders" least.  But, they do get done.

Summary:  If your user ID is "Aaabt103" and you clicked a Buy-it-Now for a headlight switch, It's probably already been shipped.
But, if you're user ID is "WhydidIbuyallthisstuff" and you won 35 auctions and want them all shipped in the same package is the receiver hitch....It's probably gonna be a day or two before it leaves.

I guess that covers my "order of things" that relate to shipping. Anybody wanna go fishing?