How do type-changing and type-dependant templates interact?

[Neowulf]

I've been working on a backup character that uses several different templates & some of them can apply only to certain creature types

My question is, how would one that requires a human work if that human was also an unseelie fay?
also, would it work to take one that changes the type you just changed into? like, would it work to take one that changes a construct into a fey, then a fey into a plant?

[Echch]

I believe that templates can be applied whenever the conditions are fulfilled. As such, if a template requires a humanoid, but that humanoid became a fey, it doesn't work despite the fact that the fey used to be a humanoid.

If a template requires a fey, however, you could apply it, even if the Fey used to be a humanoid.

[ryu]

I believe that templates can be applied whenever the conditions are fulfilled. As such, if a template requires a humanoid, but that humanoid became a fey, it doesn't work despite the fact that the fey used to be a humanoid.

If a template requires a fey, however, you could apply it, even if the Fey used to be a humanoid.

Generally true. Do keep in mind however that there are examples where a being can be forced to hold two usually mutually exclusive types. For example any demon made to switch out of evil still counts as evil in addition to the new alignment. They'll activate any effect that keys off either for positive or negative results. This means a good succubi is hosed by pretty much every protection circle, but can also get into things which require good AND evil prereqs in the same build.

[Inevitability]

Unseelie Fey doesn't say it removes subtypes, so you'd get Fey (human) (augmented humanoid). If a template requires being human, it can still be applied. If it requires being humanoid, it can't anymore. If it requires being a fey, it can now.