Retro Mode cleared achievement in lvl10

[VanAlphen]

I was trying to beat my highscore in level 10. I played through the credits and then suddenly I got the achievement for clearing Retro Mode. I've not actually cleared level 11/Retro Mode yet.

[Vance Finiraldi]

Then, it's possible that due to the mis-titled level achievements, the dev may have applied the Level 10 completion achievement (the one labeled as LEVEL 11 CLEAR!) to the actual Level 11, the Retro Mode stage and thus swapped their achievements.. I'll try to complete again and see if that's the case, but I only managed that before out of pure luck, so no promises. DX

[VanAlphen]

Could be, I still need LEVEL 11 CLEAR! and haven't managed to finish retro mode yet. I think wave 96 or 97 has been my max. I must have tried it for hours and it's my least favourite level. I also have no idea how some have achieved such high scores on this level.