It depends on the user and their tolerance, etc.
However, if you keep going back and forth between using and suboxone, eventually, the suboxone starts to work less and less. It becomes a lot harder to transition onto the suboxone after one has gone back and forth many times.
It is not made for what you're describing, using it the random days you don't have dope. It won't work like that.
In the beginning, it will work.. if you're sick and you take some, you'll be fine... but then once you decide to quit for good and really need it, it will not work, because like I said, switching back and forth fucks with your receptors and it becomes 10x harder to get on the suboxone.