https://www.warcraftlogs.com/reports/VKk8w3tp7na6XfcQ/#view=analytical&fight=16

I'll try and clip the actual combat log later.

This is most likely because BW tries to predict the target during the cast by checking the target of the boss.

Even though it keeps rescanning for 0.5 seconds if its current target is the tank, I have found an example where she does not switch her target until the very end of the cast. Sorry for horrendous quality, I screen captured it from Twitch: https://gfycat.com/JampackedRaggedFlatfish

Maybe don't announce prediction if its on the tank? I think it'd be better to announce only once the target has been confirmed.

I think the optimal workaround would be to do leave the prediction as is but if it returns a unit that's currently tanking the boss, fallback to announcing when the debuff is applied.

If you happen to raid before a version with a fix released, here's a quick fix, open WoW/Interface/AddOns/BigWigs_TombOfSargeras/SistersoftheMoon.lua, delete the following line:

self:GetBossTarget(printTarget, 0.5, args.sourceGUID) -- Faster than waiting for debuff/cast end

And replace this:

function mod:LunarBeaconApplied(args)
	if self:Me(args.destGUID) then
		self:SayCountdown(args.spellId, 6)
	end
end

With this:

function mod:LunarBeaconApplied(args)
	printTarget(self, args.destName, args.destGUID)
	if self:Me(args.destGUID) then
		self:SayCountdown(args.spellId, 6)
	end
end

@elvador bossScanner seems to not allow itself to be called for longer than 0.8 seconds:

I know, but looking at videos I couldn't find any occurrences where it actually took longer than 0.5s, so the bump to 0.8s might be enough. If the problem still occurs we might need to change the value in BossPrototype.

I think if it keep occuring, we'll have to prevent the targetscan from announcing the tank at all in this case (As it cannot go on tanks, unless they are the last ones standing) and just announce it once the debuff is actually applied as a fallback, because there wasn't a target found before that.

I've increased the timer it waits in d64c5c7. This should fix the problem. If it still happens, please report back.

@Zireael-N Your quick fix wouldn't have worked because the printTarget func is defined after mod:LunarBeaconApplied.

I posted an example of the boss switching targets 1.4 seconds after the cast started in this reply. Personally, I don't think it is worth to keep scanning to get a notification 0.1s sooner, but I didn't actually profile anything. So, +1 to @Justw8's suggestion.

it's worth to keep the scanning because there is the potential of a 1.5s warning before any debuff goes out. The late announcements are an exception, not the rule, from what I've seen.

I meant scanning for up to 1.5 seconds, could've worded it better.

Didn't see your gif, fixed it with 93932d2.