dRofus has dedicated functionality to update Model name in an effective way.
Before moving forward we recommend reading: Use Model Name to work with multiple design models
1. Divide Model A in to two new models:
In the example below we have our original model “A” which is linked with dRofus. The objects are dividend in ‘X' and ‘Y’ that is linked with dRofus and grouped under Model Name 'A' in dRofus.
Model ‘A1’ containing objects “X”
Model ‘A2’ containing objects “Y”
2. Update object with new Model name
When Model Name has been set for the model it’s works as a filter when you synchronize - ensuring you can only sync Rooms or Occurrences in dRofus that are either part of the model you synchronize with or Rooms and Occurrences in dRofus that do not have any Model Name set. In this scenario this filter prevent us from updating object ‘X' and ‘Y’ as they are still connected to 'Model A’ in dRofus.
Update:
Select the occurrence that you would like to update.
Select synchronizing
Select tick the box “Move occurrences to this model”
This option is available when synchronizing occurrences from;
Items <-> Families
Sync Selected Instances
Sync current View
The result of this sync operation is that new model names are created in dRofus and the objects ‘X' and 'Y’ have assigned new Model Names;