I was just wondering how long can you freeze a cake before taste and texture are altered?

For me I keep cakes usually 3 weeks in the freezer and it's taste as it baked today

I don't know if it can be kept more than that

As long as it's properly wrapped to prevent freezer burn, there should be no difference in taste and texture.

First anniversary cakes are frozen for a year successfully as long as air doesn't make it up through the bottom of the uniced portion between the cake and the possible board it may have been frozen on.