I've just run five additional tests with two households and I've dumped the sim object identifiers so you can see the correlation. Household 2 was used for the first four tests and Household 1 for the final test since I've used Household 1 for the initial test. In each test I've placed the members of each household on random lots throughout the world in different neighborhoods and in every case the lot where the sim with the oldest object identifier has been sent is the lot which I am returned to:
Household 1
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216176111160393823 Eliza Pancakes
764489382074253459 Plethora Jalowitz
Household 2
===========
764489382074253455 Yelena Gabrielsun
764489382074253456 Holly Gabrielsun
764489382074253457 Magdalen Moon
764489382074253458 Quanta Jalowitz
1065104640786759691 Noelani Langsford
1065104640786759692 Barbara L'Amour
1065104640786759693 Eternity Charvat
In this list of IDs you can clearly see that Eliza Pancakes and Yelena Gabrielsun have the lowest (oldest) object identifiers. These IDs are generated when the sim is first created, they are globally unique, and they can never be changed. You'll also notice that Plethora Jalowitz has an ID which is sequential to the first four from Household 2 and this is because she was created as a member of Household 2 then moved into Household 1.
From the test we can conclude that the oldest sim ID is retrieved when the 'current zone' is queried during the "Change Outfit For..." interaction. To solve the problem, the object containing the "Change Outfit" function for closet objects must be overridden in a new package (also known as a patch to us laymen).
