The new Liberation of Undermine raid has a boss with a mechanic that erects LoS walls around an area (and some people will be in it, some out). When I was doing this fight tonight with Grid2, I could only identify who was in or out with an associated debuff - everyone still showed as "in range."

I mentioned this, and found out that some using other addons were seeing those not matching their phase go "out of range" after a second or two. A fellow healer (using Cell) told me that this was actually smart enough to show only those in his own ring as "in range," while even the others in the other ring (who had the same debuff) were shown as out of range. I couldn't verify this, though.

Here's a picture from a stream of someone standing outside of both rings, and you can see that the addon (looks like ElvUI to me, though not 100% sure) is showing all those in the rings as "out of range."

Here's a similar picture from my raid tonight, where (even though I'm also outside the rings), no one is OOR for me. This same issue happens when I'm inside - everyone shows as inside range, and I just have to know (or guess) who is in the circle with me.

Is this something that could be supported in Grid2? Here are pictures of my alpha indicator and range status, if that helps any.

Using Grid2 v2.8.73 on WoW Retail 11.1.0.59538.

Confirmed that the 38y option does work on this fight. Thanks for the clarification on the options!

As far as i know cell and elvui dont have any special case for this boss, and all raid frame addons are using similar code to check the range. Are you sure they are not using some kind of weakaura to fade out the player frames ?
Did you try out with 40 yards range instead of heal range ?
Can you confirm if in this case the party members that are not in your ring cannot be healed (heal spell cannot be casted on the players) ?

A friend of mine uses Grid2 as well and said hers was working correctly, when using the 38y status option for Range. I'll give that a shot next time and let you know. Thanks!

The 38 yards option uses similar code to standard blizzard frames / Cell / ElvUI, using the UnitInRange() function, but this method does not necessary check if the target is really heleable, only if the target is inside a standard distance: ~40 yards for most healers and i think about ~25 yards for evokers.
But the Grid2 range "heal" option checks if a specific heal can be casted on each unit frame (for example for paladin the code checks if the flash of light heal can be used on the unit), so usually its is better/more useful for for healers.
But it seems that in that specific boss phase, this kind of check is not useful because the game reports that all players can be healed.

Gotcha, thank you for that clarification! I'll give the 38y option a test next time I'm in there to see. Sounds like something I'll have to remember to swap back and forth just for that fight.