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I would keep the Magnet and ED where they are right now. The CLI opportunity does not expire.
When you app the Hilton, it is quite possible AMEX makes a reallocation, and you won't know which card, either Magnet or ED, they might pull from, until they do... or do not.
By leaving the Magnet alone, you don't poke the bear about "closing a card early" and reduce your risk of getting boxed out of the SUB on the Hilton card.
You can reallocate limits after the Hilton app.
Since all three cards are probably no-AF, there is absolutely no rush to close any of them. Slow and thoughtful, planning carefully, is my advice regarding AMEX changes.