I would caution you on putting oil on it at some specific interval. Only put it on if it is needed. Too much oil on a fretboard can cause havoc. If you are playing it a lot, you probably don't need to oil it at all. If you do oil it, you want the least amount of oil on it you can apply. Don't leave any excess on it. I own more than my fair share of guitars and I use Fret Dr. rosewood bore oil. I have some guitars that I have never had to put oil on and others that I oiled one time. I am not sure if I have any that I have ever oiled more than twice, and this is over a couple of decades of owning them. I think people get too carried away with oiling fretboards. This is actually a concern of mine when buying used guitars.