Some anecdotal notes on a slurry lag time experience with simple yeast storage from this weekend.
I brewed a blonde ale, yesterday. Finished brewing ~2pm.
A quart jar filled with 2nd generation Nottingham slurry harvested on 3/5 was taken from the fridge and set in a dark spot on my kitchen counter ~11am. My house was at 70F.
I collect slurry via 5oz long handled stainless ladle from the bottom of my kegmenter post fermentation. I generally pitch and rack to a keg after 2 weeks and then collect slurry.
It was 1047PM before my kegmenter came down to 67F in my fermentation fridge. I had ran 10 gallons through an immersion chiller to knock the temp down a bit, racked into the kegmenter and put it in the fridge to continue cooling. 1047PM is when I pitched by pouring off most of the liquid, swirling the yeast into suspension a bit and pitching straight in.
The temp was set to 64F plus 2/minus 0 with an inkbird probe taped to the kegmenter w/ a couple layers of masking tape.
I woke up at 627AM and blowoff was bubbling @ ~ 2 bubbles per second and the probe temp read 64F.
Maybe notty is better suited for this. But I guess that is the problem - too many variables. The yeast strain, length of storage, previous brew strength, etc. if you are a brewery doing the same brew on the same schedule with the same yeast, you can find a repeatable solution. But homebrewing, forget it for me.