*EDIT* as referenced in replies, you don't have to re-buy the updates. Itch's UI is just weird and shows the buy button regardless of if you bought it already or not. *END EDIT*
Is there some way I can get these updates if I've already purchased this pack? Buying each new update separately is a little odd. I'll gladly pay extra for the privilege. Otherwise you're kind of incentivising people not to buy the first release of each pack (e.g. your new crops pack) if the later improvements are going to cost the same anyway. The other commenter was a jerk, but I also genuinely didn't think "in-development" meant later updates would need to be bought separately.