Rest arcana - whole rest in anacrusis

I'm doing a piece in 2/4 time. I had the first few fresh measures after a volta with whole rests in them, and changed the length of the first measure to one 1/4 note length. The rest symbol stayed as a whole rest, just like in the following measures. Of course, I see how it comes about, but the reader has no idea that the duration should be half a measure... I guess that with an anacrusis, a whole measure rest should switch from the rubber whole rest to a rigid rest... Of course, the user can just change it, which I did. Just mentioning it as it was an amusing bit of arcana.