Slight modification of this question.
This question resolves YES if the Elgin Marbles (aka the Parthenon Sculptures) are returned to Greece by the end of 2029, and NO in all other cases.
The method of return does not affect resolution; the majority of the collection entering Greece on loan, as a gift, after being stolen, or after the UK being annexed as a Greek colony would all resolve YES.
@mariopasquato Yes, these criteria are copied from the earlier question, but I interpret them as saying all most of the marbles have to be returned, not just a few.
@mariopasquato Actually, ninja edit: the second paragraph says "majority". I interpret this as meaning greater than 50% of the contiguous pieces of marble that exist in the collection.
@BoltonBailey Looking at wikipedia, I can't tell exactly how many pieces there are in total, maybe around 36? I'll look into it more closely if there's a claim this should resolve YES.
@mariopasquato Lol that's a funny bit from the criteria, I guess the answer is that in that case, they won't even have to be returned to the traditional Greek territories since the UK will technically be Greece.