The .io registry is operated by Identity Digital which is a consolidation of a bunch of different registries from the last decade[1]. Identity Digital own (and sometimes just operate) many different TLDs and ccTLDs: most likely, the registrar will retain the right to operate the ccTLD and start paying license fees for each .io to Mauritius. The .tv ccTLD is the most famous example of this, as something like 15% of Tuvalu's GDP is from licensing of the .tv ccTLD.

[1] ICB acquired by Afilias, Afilias acquired by Donuts, Donuts rebranded to Identity Digital.