I'm having the same issue. When it runs the error check, it changes my itemized charitable donations to $300 rather than changing it to $600. It has to be a bug. When it runs the error check and changes the deduction to $300, you can watch your return reduce. It shows the error, I make the change to $600, and everything works...unless I run an error check again. I can definitely delete the itemization and just put in $600, but I itemize to ensure I'm not going to have deductions higher than the standard deduction. We shouldn't have to itemize, and then delete it again.
