Hello Saanvi,
No, the version 0.16.06 Premium is no the completed game.
There are the first true endings on writing in the Premium version, but sadly the game is yet far from being finished.
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I don't know.
All I can tell is the main story is already written (at least the Neus Route). lacks illustrations on the Epilogue, and then finish the unfinished parts and also the whole Blondie route.
Last year I thought I would finish it in a year, so if you ask me now, I would tell you the same as last year, and probably I will be wrong again.
But I doubt I will finish it soon.