I'm new to MTW so I'm wondering, If I upgrade my fort/castle/etc. to the next tech lvl w/o buying the defense upgrades of the previous lvl (for example: Not buying the motte/motte and bailey upgradges before upgrading your fort to a keep) do I lose the ability to buy those upgrades, or can I still get them?


On a related note, when buying the new artillery pieces for castle towers, are the old pieces still there or are they torn down to make room for the new ones?