Hi blocky
A Sarracenia alata x purpurea will always be an exornata no matter which alata is crossed with which purpurea, like a flava x purpurea will always be a Catesbaei. but a cultivar is generally a designated plant and is generally described in the published description, as not to be reproduced by any other means other than division to maintain the individuality of the cultivar, so a designated description and plant type should exist. Even with a description you can get cock ups and multiple plants in circulation S. 'Evendine' being a case in point, leading to many different looking and genetically diverse clones having the same name. Confusing eh.
There is no cultivar S. 'Peaches' registered at the ICPS as far as I can tell, however there do seem to be a lot on sale as cultivars, indicating that there has been some description and type published somewhere, possibly from the 1980s although what this is, where and exactly when I can't find, if anyone knows please let me know. So whether these are the genuine article 'Peaches', or some derivative of an exornata, or even some legacy of '"Peaches and Cream", which incidentally I have seen written in single and double quotation marks, but there is no cultivar of that name registered at the ICPS either, I am not sure.
Welcome to the confusing world of Sarracenia
Cheers
Steve