I’m working in philosophy, where it’s common to collect the papers one has written in anthologies. I want to cite multiple chapters from such an anthology, all of which have been published as papers before. I have added their original publication date in the “Extra” field. Using the “Chicago Manual of Style 16th edition (author-date)” style, last updated on the 4th of October 2015, I get the following references:

(Haslanger [1993b] 2012; Haslanger [2003c] 2012; Haslanger [2007a] 2012)

This is how the corresponding bibliography entries look like:

Haslanger, Sally. (2007a) 2012. “‘But Mom, Crop-Tops Are Cute!’ Social Knowledge, Social Structure and Ideology Critique.” In Resisting Reality: Social Construction and Social Critique, 406–28. Oxford: Oxford University Press.
———. (1993b) 2012. “On Being Objective and Being Objectified.” In Resisting Reality: Social Construction and Social Critique, 35–82. Oxford: Oxford University Press.
———. (2003c) 2012. “Social Construction: The ‘Debunking’ Project.” In Resisting Reality: Social Construction and Social Critique, 113–38. Oxford: Oxford University Press.

That is, the letters that should be added to the publication year to resolve ambiguity are added to the original publication year instead.

I’m using Zotero SA 4.0.28 on Mac OS X.

Could you fix this if you get around to it?
Thanks a lot!