Disable Multiple Selection of Production Orders

Hello all,

We would like to issue a dialog box to users who are releasing / starting production orders en-masse. Some users need this ability, while other users are unaware of what they are doing.

We would like to place a dialog box to alert the user of what they are doing, above the ProdMultiStartUp dialog. And, only if more than one order is being updated.

Where would you recommend is the best place to inject our code?