There is noting "scammy" about it (misleading perhaps). This particular seller is probably afraid that people are not going to manually extend their processing time, so he most likely does this out of fear, when he should just say it like it is. Many people don't understand the fact, that NO seller has stock of this particular IEM, because IT'S CUSTOM MADE. You place an order, the seller takes it to BGVP, they manufacture it, then send to seller, and then aliexpress takes care of the rest. I would actually blame people who are not familiar with the process, and jump to conclusions and bash sellers out of frustration. I've had a long discussion with that seller, and he never used such an excuse on me, because I showed him from the start that I understand how it works (and that I will extend the processing time, especially after the huge number of orders). I'm not making excuses for him, and he probably should've said to every person that ordered (yeah, each of all of the 400+ orders), that they will need to extend the processing time, because of all that. And keep in mind, that every order that gets canceled hurts the seller, because there is already order placed with BGVP, and when an order gets automatically canceled, it hurts all parties involved (the seller, BGVP and YOU).
My recommendation to all: give the seller (all of them in fact, because they are all affected by the demand) 20 days more processing time (and extend additionally if needed), and learn patience. There is a language barrier as well, and that contributes to the confusion, No reason to be negative. You will get your order eventually.