Are legacy/old litchi apps versions still working by chance? Is it still doing license authentication or allowing you to escape and continue to use the current version? If so, at least and generally with old software if you ‘update nothing anywhere’ at this point, it should continue to function as it has(except for licensing servers still being demanded that no-longer exist).
Lesser apps than Litchi have made their own licensing servers/.apk’s to be free of App-store restrictions, maybe Litchi could do the same.
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