Is this a total freeze that the game never recovers from (meaning, does it actually crash and produce a crash log) or is it more of a long pause?
Usually a total freeze/crash reproducible at the same sim time indicates something is scheduled to happen at that time and it's overwhelming the game engine. Common things at around 11 am would be
-- Sims who begin work at 12 noon are spinning into their career outfits and trying to go to work. The culprit could be a "bad" career outfit including "bad" CC.
-- A Role Sim is scheduled to begin staffing their object but they are stuck somewhere, perhaps trying to age up in private, and the game gets stuck trying to force them to do two things at once that they cannot do. Register usually helps sort this out but sometimes I still find Role Sims standing still on a sidewalk or someplace unable to move when they should be at their stations and the first thing I do is check their ages to see if they are indeed overdue to age up.
-- Way too many spawners somewhere in the world set to go off at that hour.
-- A sim somewhere in town is in labor at that time and stuck in the infinite birth loop glitch (the mere presence of Woohooer should put a stop to that).
None of those are really SP specific admittedly, but in an indirect way SP could be managing sims' careers and pushing pregnancies to the extent that these things wouldn't really have taken place otherwise. If you remove SP and clear the script cache, does the 11 am freeze immediately stop happening?
If that doesn't seem to be any help, perhaps you could bring the issue to us at NRaas together with any ErrorTrap and other script logs so we can assist with narrowing this down a bit further. There are some debugging alarm dump tools we can suggest to get a log of whatever else might be scheduled to happen at that hour.