1_X seems to have stood for POTUS' Twitter phone in the past.
Edited version. Thought I might be able to get some detail outside the windows by turning the highlights down but they were too blown out.
Slightly different though. There's a gap between the screens in the pic you added where there's no gap between them in Q's version. Nothing major though.
Initially when I saw Z I thought of Zulu time. The image name had Z9 in it. 12 minutes till 9 PM Zulu time.