I'm at about 12 hours and still seems like lag phase to me. Granted I'm in a bucket and judging by the creation of small bubbles on the surface of the beer along the outer edge. My assumption is that when I see these I'm probably about 3 hours past lag phase. This is a 1.058, 5.25G batch so I expect a full lag phase with a single sachet of yeast. Based on my previous attempts with MJ yeast, I'm expecting about 24-30 hours lag.
I've seen posts from folks that have stated a longer lag phase when rehydrating versus sprinkling dry. But, again, I'm not sure how much lag phase is indicative of anything wrong with a pitching rate unless you start getting into the really long times (36+ hours). I think we're all just paranoid about contaminants having a chance to run rampant (that's why I'm mostly concerned with it), but I figure as long as I feel like I had a good sanitary process then I should have some leeway. Additionally, I believe that temperature is going to play a large roll in lag time as well. The warmer the wort the shorter the lag. I pretty much pitch everything right around 61F, and no higher than 64F.
Anyway, I'll post back when I see activity.
Edit: Started seeing bubbles/krausen around 2-3 so I'm guessing lag was over about noon, which makes the lag phase about 15 hours this time; give or take 3 hours or so. Definitely the shortest lag phase of the three sachets of MJ yeast I've used thus far.