I am seeing this too. It confuses members of the family - they are accustomed to looking for a particular picture when finding a recording in the list, not having to read every icon. This happened last night with "Last Man Standing". Instead of the LMS photo icon, it had a generic ABC.
Been having this issue for a week now. Still no icons. Had to recreate every timer as none of the existing timers will recognize anything in the current guide data.