Here's this month's photo story chapter summary. Like gordol mentioned, it seems they're focusing on the Oldrin side of things this time. According to the info he posted, this chapter occurs immediately after the end of the current Knightmare Ring arc and features a "Lancelot Grail vs Lancelot Trial" battle.
Spoiler for Oz Photo Story Ch 13 Summary (Extended):
Code Geass: Oz the Reflection (Photo Story) Chapter 13
They are protecting a small remote town within the Mongolian Administrative District in the northern Chinese Federation from a militia group. Orpheus accepted this mission, to the point where he refused a high priority mission instead, for a reason. It is because he has a debt that he owes from when he escaped from the Geass Order with Euria in the past.
In the town, Orpheus meets a female Britannian knight called Neris. Due to the course of events, he sets out to fight the militia group along with her.
Spoiler for Oz Photo Story Ch 14 Summary:
Code Geass: Oz the Reflection (Photo Story) Chapter 14
Having been recognized for its distinguished service in Area 11, plans follow to mass-produce the Lancelot. At the California armed munitions Rhongomyniad Factory, the open test of the Lancelot Trial is about to start with the Imperial Family asked to attend.
(TL Note: Rhongomyniad is the name of King Arthur's spear, which means "spear" + "striker, slayer")