diff --git a/ayanova/devdocs/todo.txt b/ayanova/devdocs/todo.txt
index 80e0ff59..80c35a7c 100644
--- a/ayanova/devdocs/todo.txt
+++ b/ayanova/devdocs/todo.txt
@@ -101,13 +101,18 @@ todo: PLANNING workorder data and class and route structure:
 	Need to go over all wo features and factor them into this decision properly
 	The whole idea of a completed section of a wo and stuff, is that dropped due to TTM or still viable?
 		maybe can pick out the best new features of that which can be integrated into existing design rather than re-inventing the wheel
+		Here is an overview: https://rockfish.ayanova.com/default.htm#!/rfcaseEdit/3412
 	How best to be able to service LoanUnits on a workorder?
 		Just make them Units with extra properties exposed if type of loaner?
 			This seems simplest, but what will it effect?
 		Hard to make them serviceable if they are an alternate table of source for what's being repaired as that breaks a lot of other code or adds exceptions
 			Customer is then who exactly because it's fundamental to a lot of wo functionality?
 			from a biz perspective isn't it like you are your own customer when you service your own equipment that you loan out?
-	
+	Does Serial field need to be numeric, could it be text instead?
+		prompted by case 3428  saying that it's hard to deal with constant conversion to text for UI etc
+		plus, I'm thinking it opens door to textual scheme like appending -A or whatever to a wo.
+		or, is that a display issue?
+		Calling something "serial" implies it's unique but it isn't, maybe I should call it "number" instead or "ID" or something?