That depends on how much oil your putting on the bat in one coat, i normally apply a little amount around 2-3 times before and during the knocking in period. Its always best to under oil a bat rather than over oil and i find some bats need more than others.
My way is to add a small amount across all areas of the bat apart from the splice, i always leave it to dry for two days and always in a parallel position and once fully dry i decide if more is required as some bats dry out quickly. I then add another light coat and repeat the above steps and then start knocking the bat in, once the bat is ready i give it a light rub down and possibly another light coat prior to full use.
I have to also say at times I've not oiled the face of the bat at all and I've added a anti scuff straight away and oiled the back and edges and this worked really well.