BBB @ MK strategies?

[kjs1976]

My dear friend is taking her princess obsessed 4 year old to WDW for the first time in October. They just finalized plans and the only BBB time they could get was 1:45 PM at DTD on their MNSSHP day. Having never done this with our DD, I said I'd ask here on the Dis if there were any strategies to getting an open slot at MK..such as how often to check back or...? Any advice on this would be great. TIA!