Anyone else's lights been flickering every night at the exact same time?

Right so this has been bugging me for a while but yeah, same thing happening at my place in Essex. Every night around 11:40 the light in my hallway does this slow flicker like its struggling to stay on, lasts maybe 30 seconds then stops. Been happening for about 3 weeks solid.

Before anyone says it - I already checked the bulb, checked the wiring as best I could, nothing obvious. Electrician mate said the circuit looks fine.

The time thing is what gets me. If it was a dodgy connection it wouldnt be that consistent right? Like random faults dont follow a schedule. Has anyone actually tried logging the exact times and cross referencing with anything like lunar cycles or local EMF readings? I picked up a cheap EMF meter and I'm gonna start documenting it properly this week.

Anyone else getting this? Especially curious if anyone elses is also late at night rather than during the day.

@james_cromwell hang on, also in Essex - whereabouts are you? Not asking for your address obviously but wondering if we're in the same area because that timing is weirdly specific.

Have you actually logged the exact times over multiple nights? Like written them down rather than just estimating? Because in my experience with poltergeist cases the timing can drift slightly and you only notice if you're tracking it properly. If its genuinely locked to 11:40 with no variation thats either electrical (worth ruling out first, check your fuse box logs if your consumer unit records them) or something worth paying proper attention to.

What kind of bulb is it, LED or old incandescent? LEDs can sometimes pick up interference that older bulbs wouldnt.

Not to rain on the paranormal parade here but before anyone goes calling an exorcist - has anyone actually logged the exact times over multiple weeks and checked against local grid load data? Power companies publish this stuff. Flickering at the same time every night is almost always a voltage drop on the local network, usually correlates with peak-off cycles around 11-11:45pm when industrial draws shift. I had similar in my old house in Sleaford, drove me mad for months, turned out to be a substation issue three streets away. That said if you've already ruled out electrical and its genuinely consistent to within seconds night after night with no variation, that does get more interesting. What's your tolerance either way - are we talking within 5 mins of 11:40 or bang on to the minute?