According to a forum post, the team at CD Projekt RED have pinpointed an issue that apparently is keeping players from getting rewarded XP when they finish certain quests that are six or more levels below them. So the studio are now looking into retroactively rewarding players the XP they should been hoovering up, according to the studio's community lead Marcin Momot. However, it's important to note, Momot isn't making any promises just yet.
"One more thing regarding this issue," says Momot. "It doesn't affect every quest but only some of them. That's how we know the experience loss is not that big in total numbers.
"It will be fixed however. We are also looking into the possibility of gaining the missing XP retro-actively by the players. Can't promise anything here though."
A patch will be issued out to PC this Monday.