Voucher Build deletes all rows out of staging table

Our business has found that in order to use Voucher Build (Financials 9.2) multiple times a day, they must follow this order: Upload, Build, Upload, Build.  When they try Upload, Upload, Build, Build the second build always fails as some of the staging tables have been wiped out.  My business always uses control groups when running Voucher Build.

I am just wondering if anyone else has run across this issue and if you have done anything to fix it?  (we've been processing this way for 5 years or so)..

Thanks,

Karin