When working with ArcMap Advanced Drawing Options (ADO), the order of the symbols may change unexpectedly after changing a symbol. This also changes the drawing order of symbols in the data frame.
Once you have turned on ADO for a data frame, if you make changes to your symbology the symbol list in the ADO dialog box may reorder. Changes that will reorder the symbol list include:
1. Picking a new symbol to replace an existing symbol in the list.
2. Adding symbols to the symbol list. This happens when you make changes to the symbology method for one or more layers in your data frame. For example, you may decide to increase the number of classes in a Graduated colors classification.
The best strategy when working with ADO is to finalize your symbology as much as possible before turning on ADO.
If you must replace a symbol after you have turned on ADO, do so only via the ADO dialog box. This will keep the order of the symbol list intact.
To change symbology via the Advanced Drawing Options dialog box:
1. Right-click on your data frame in the Table of Contents and select Advanced Drawing Options.
2. Pick a symbol from the list and click Symbol Properties to edit the symbol.
3. Click Apply or OK to see your changes.