Now that President Biden has specifically raised the cases of Michael Kovrig and Michael Spavor:

There is some speculation out of China that President Xi may release the pair as a goodwill gesture, citing 'humanitarian grounds' as his reason

Not doing so risks further damage to the US-China relationship that is already off to a less than spectacular start with the new US administration.

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Not directly of relevance to FX (perhaps more to AUD than anything else - China has been kicking Australia as a proxy for the US) but it does speak top US-China strains.