The TSP website used to say that IFTs may take 2 business days to be in effect. But now this is what I read and understand your frustration:
As far as recourse, I don't think you can do much. It says "generally," so there is no guarantee made.An interfund transfer requested by 12:00 noon eastern time on a business day will generally be processed that night. The new investment percentages can be viewed online the next business day.
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