I opened a bug with support (#2561809) to see if maybe LL had recently changed the clock in one of the regions, and was told to vote for this other issue: https://feedback.secondlife.com/bug-reports/p/fix-eep-mainland-environment-cycle-are-way-too-dark
That doesn't look like the same problem to me. The other issue is about overall brightness, but THIS issue is about the SUN ANGLE being different on two border-adjacent parcels for no apparent reason, when the region and parcel settings would seem to suggest that it should be the same.
Investigation so far:
Albion’s region sun position is out of sync with adjoining Noyo even with the same GMT-8 offset. On my parcels (NE corner of Albion + SE corner of Noyo), both set to Use Region Settings, LSL confirms identical day lengths (14,400 seconds) and offsets (57,600 seconds). For Sky Altitudes, both parcels report using "(region environment)".
However, late in the day, the sun is visibly above the horizon in one while visibly below the horizon in the other! The same phenomenon can be seen at other times as well.
Near-simultaneous llGetRegionSunDirection() readings put Albion’s sun about 29° above the horizon and Noyo’s about 2° below it. Each parcel’s sun direction matches its own region’s.
Reapplying Use Region Settings and relogging do not resolve this. Applying the same explicit day-cycle asset to both parcels makes them agree, but puts both of them out of sync (-8 hours doesn't mean the same sun position on these parcels that it does on neighboring parcels).
I think someone at LL may have recently changed the region settings in Albion as it wasn't like this a few days ago.
Please investigate Albion’s underlying region environment/day cycle and restore consistency with Noyo.
Phenomenon observed in both Second Life Release 26.3.0.31203661088 (64bit) and Firestorm 7.2.4 (80712) Jun 1 2026 12:24:09 (64bit / AVX2).