I successfully upgraded one feature in my existing sharepoint 2010 site collection(A) . Previous version was 0.0.0.0 and I upgraded it to 1.0.0.0. After upgrading I created one more site collection(B) and activated the same feature. To my surprise site collection(B) does not contain any changes that I applied to site collection(A). I ran following powershell script to check the version of feature on both site collection and it results 1.0.0.0 for both.
(get-spsite http://mysiteurl/sites/scb).QueryFeatures((New-Object System.Guid("--feature guid--")), $true) | Select Definition, Version
Now I can't upgrade my feature in site collection(B) because upgrade system will not work because version is 1.0.0.0. Is there a way to upgrade features in new site collection that are created after feature upgrade?