Did you mean, that on your Tableau Desktop it shows the correct Year? then when viewing on Tableau server where it was published then this year appear?
Maybe the problem here is the System Settings on the Tableau Server itself.
Thanks and God Bless.
Jonathan B. Velarde
I've seen this happen a couple years ago with date sliders but I don't remember why. Try this just to trouble shoot to see if I'm right. Remove your date slider filter and date dimension from the viz. Then replace the dimension and filter (use a relative filter)...