Blueprint requirements for pantry upgrades?

It took 1 blueprint to upgrade a pantry from L18 to 19, and I am fine with the need for a blueprint (or even 2) to do that.  But now it is requiring another 2 blueprints to upgrade from L19 to 20, is this a bug or what is meant to happen?  If so, it is totally unreasonable to require the need for 3 blueprints to upgrade each pantry in each town.  

That's nuts.

Ah, maybe to store resources when the army demands a lot (food/iron) and higher level (e.g. raw) storage isn't available yet?  If you don't think we need them, why is the option available?  Maybe the balance between food and iron production capabilities and army training/upgrade/maintenance need to be revisited.

Regardless, it seems a bit extreme to require 3 blueprints to advance any building by 2 levels.

Ofcourse you may need them, that's why they are present. I meant they are not required, that's why they cost that much blueprints. They are for those people who have extra blueprints (or money) to spare and want to squeeze extra something out of buildings. If you will find a place where level 19 or 20 buildings are REQUIRED for progress, report it and I will reconsider. From your situation looks like you could do just fine without level 19 or 20 storages so sorry, they were designed to require 1 and 2 blueprints accordingly.

 am trying to get level 8 for town hall.  requires 14780 lumber.  I have lumber shed that requires one blueprint for level 18 and one blueprint for level 18 building pantry.  my storage at this point is 12720 lumber that means i need to upgrade lumber mill and building pantry, just to get required lumber for town hall level 8. so to me it looks like the blueprints are required.

 am trying to get level 8 for town hall.  requires 14780 lumber.  I have lumber shed that requires one blueprint for level 18 and one blueprint for level 18 building pantry.  my storage at this point is 12720 lumber that means i need to upgrade lumber mill and building pantry, just to get required lumber for town hall level 8. so to me it looks like the blueprints are required.

or you can wait till you get raw storage to upgrade the town hall. You will loose shed soon when you do the research for raw.

Thanks for the reply,  but in my case they are REQUIRED or I have to just wait for research, doesn't seem quite right, and I would not mind purchasing them, but the cost is WAY to high.