BH Cru, now clasified as spectral type SC, according to 'The evolutionary state of Miras with changing periods' by Uttenthaler et al is now properly a carbon star, spectral type C. The paper is an interesting read...
The article in question is: http://arxiv.org/pdf/1105.2198.pdf
I found it interesting reading with discussions on Mira change types, spectroscopy, Tc, Li, convection and thermal pulses. The article even quoted AAVSO data and an AJ article from 2005 by Templeton, Mattei and Willson. Kevin Paxson - PKV
I am especially fond of this star because of one of it's other names! :)
But it wasn't my discovery - it was Ronald G. Welch's discovery!