If it's a summary report, can you see the records it is summarizing? Whichever records are missing on one of the two views should help troubleshoot.
It would seem to me that somewhere down the line (perhaps you are using lookup or otherwise related fields to calculate?) there is a restriction for one user, and that is limiting a view. I believe there is a field setting that is something like 'Use these permissions even if they are less restrictive'. Check to see if that option is available in the fields you are using in the calculation.
Also I would check to see if there are any filters on the report you are looking at.
There should be no delays. Others on this forum know a lot more, so maybe someone else has ideas!
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Mike Tamoush
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