Wont really make a difference, if youre into BA (Gen) or BA (Hon), incase youre aiming for UPSC. However incase you plan to pursue Masters besides continuing UPSC Preparation, maybe BA Hons might just give you a slight advantage with respect to MA Admissions in Top Central Universities. BA hons is more specialized and inclined towards your subject of interest, while BA Gen is generalised. BA Gen might just help you save time, but I would suggest you to pursue BA Hons, and explore your subject of interest, which may perhaps become your Optional Subject during UPSC Examination and help accordingly.

For more information about BA Hons do follow the link below

https://www.careers360.com/courses/b-a-hons-bachelor-of-arts-honors/amp