Riggs wrote:The relic is unveiled at the start of any turn.
During the shooting phase effected units reroll 1s to hit and wound
Do you check to see who is effected at the start of the turn, or during the shooting phase?
You check if you're within 12" whenever you make a to hit or to wound roll with a unit, regardless of what phase it is or what you're doing, for the remainder of the turn. You don't just check once at the start.
It doesn't say "During the shooting phase". Please make sure you've got the rule right before asking questions about it, as otherwise it just leads to confusion and incorrect answers. Working from memory is a mistake even I all too frequently make!