So I accidently got a legendary for a wrong spec

[Turtel]

Blizzard haven't given a detailed enough explanation of the system to be able to say for sure, but I doubt there is a separate counter of BLP for each spec. If that were the case, then it would be possible to have a higher chance to get a legendary on a spec which you have a lot of legendaries on, than a spec which you less legendaries on, depending on how much time you spent collecting BLP for each spec, which would lead to a contradiction (since Blizzard has stated that you have a higher chance to get legendaries on a spec which you do not have many legendaries on).

What would be more consistent with what Blizzard has stated would be if you simply had one quantity for BLP for your character, and this affected the drop chance for all your specs. The thing that differs between specs would be the base drop chance of getting a legendary (the drop chance before being affected by BLP). This would also be a lot less complicated way to code it, since it would simply use the same variables as before, rather than creating a whole set of new ones to track BLP for each spec separately.

In other words, in my opinion, yes, you have reset your BLP counter, and need to accrue it again before you have a decent chance to get any legendary. The positive side to your situation is that swapping to Windwalker made it easier for you to get that legendary, so now you have more legendaries (on average) than you would have had if you had stayed on BrM the whole time.

[Marrilaife]

Well I don't know exactly how BLP works, but I got 1st legendary for WW for my monk and then immediately switched to BM, got 1 super fast, switched to MW, got another 1 super fast, switched back to WW and got my second one not that much later (as you'd expect for 2nd legendary not 4th). I'd swear spec-specific legendary separation went live in 7.2.

Only thing that is planned for 7.2.5 afaik is the fact you can get offspec legendaries without changing your loot spec if you exhausted mainspec options (atm you just get nothing).

[Polarthief]

I get one WEEKLY* (*once per ~5~12 days), and I have every Balance/Druid-wide legendary. Just got my first Guardian-specific legendary last night. From Elite Strikes (5 turnins per each one done, and I can complete 3 per CC), doing every WQ on Broken Shore, never missing an emissary (sometimes stockpiling up to 3 days worth and doing them in one day), and doing just a full clear of Heroic NH (and sometimes getting a Mythic kill if we progress; we save our lockouts til we get Gul'dan). Also a single M10+ every week for my 905. That's it. No heavy grinding or anything.

Even if your BLP is reset for all specs, it's really not the end of the world if you just do a raid a week and get all Legionfall supplies you can.

[Onikaroshi]

It does when it's a shared one like sephuz or cinidaria, if it's something that doesn't drop for brewmaster spec, then you're safe.

Oh yea, barring that stuff, figured people would be smart enough to put 2 and 2 ya know :P