Boards
Not that big a deal.
(NOT.... Not that big of a deal.)
I'm excited /about/ a time when this extra 'of' nonsense stops.
(NOT.... I'm excited /for/ a time when this extra 'of' nonsense stops.)
Did you use to say and write these things correctly at any time in the past?
(NOT.... Did you /used/ to say these things correctly at any time in the past.)