Hi Jonathan,
I would also recommend creating a new record since it's a brand new loan. I have had this very situation come up a few times in the past. In my mind, establishing a new record makes it clear when this object arrived at your institution this time, what the purpose is for it being there this time, and as you mentioned, what its current condition is. If the old record is just edited, it will be less clear that the original loan actually did end and this isn't just a much later extension. For basic description of what the object looks like or its dimensions, you can certainly copy and paste into the new record to save time, but creating a new record keeps the other loan details distinct and up-to-date.
If you do just edit the original record, make a very clear note as to when the first loan ended, that this is a new one, and what the details are of this new loan. This may help alleviate any confusion down the road.
Best,
Angela
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[Angela] [Stanford]
[Independent Registrar and Collections Specialist]
[Advanced Museum Services]
[Indianola] [Iowa]
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