```ruby
Time.now.year - (Time.now.year - 6) == 6
```

The issue here is that we have a test repo with 30 commits made in November 2007. The test case is attempting to find all of those commits using the 'since' function. Hardcoding the '6 years ago' doesn't actually help, since next year all the commits will be 7 years ago. Instead, hardcoding the 2007/2006 seems to be the easiest way.

(Your point about `Date` vs `Time` is handy to know, though)