Check out these images below, as it appears that we will be getting a new Legio Custodes upgrade kit coming.
Thank you Alpha Operative for noticing this and sending us your finding.
Sent in by a reader here on Faeit 212, you can see his post on Bolter and Chainsword as well.
http://www.bolterandchainsword.com/topic/330199-hh-weekender-schedule/page-2#entry4632516
I noticed an old school bolter wielding Custodian (straight from the pages
of Collected Visions) in the lower left corner of Inferno's cover.
Looks like it's a yet unseen upgrade kit for plastic Custodes!