Yeast Concern This Morning

Started an oatmeal stout this morning and noticed after starting and smacking my yeast pack at 3 a.m. that is said to being a start a day or two in advance. After reading Wyeast's site last night and not putting two and two together until this morning, I realized that this might be an issue because of either 1) the SG might be around or slightly over 1.060 or 2) it's a 5.5 gallon batch?

And suggestions. I'm right in the middle of this now and another smack pack might not be an option today. Can I pitch another pack in a day if nothing is happening?

Fermentation can take up to 3 days to start if you didn't make a starter first. Don't worry about it- it should start up in the next 24 hours or so.

Here's some good info: https://www.homebrewtalk.com/showthread.php?t=43635

That was what I thought, but being only my 4th brew, I just wanted to make sure I don't bungle it!

I would think you should be fine, but if you have some extra DME laying around you could make a starter today and pitch it tomorrow.

Out of sheer laziness and/or bad timing, I've pitched smack packs without starters, and while fermentation took a bit longer to start, the batches turned out fine.

If your yeast pack was manufactured recently you should have no problem with fermentation.
RDWHAHB!

try to really aerate the wort too. the more, the better (unless you have pure Oxygen).

more air means the yeast will have more time to reproduce to an optimal colony size when you pitch. it does mean more lag time, but I've had beer that took 3 days to start fermenting, and ended up being excellent beer, free of off flavors.