A couple of months ago I had air vents indstalled into my roof to let some ventilation in the roof as the under tile felt is now elligal solid plastic which doesn't breath like modern felt. Last week, I noticed that the vents were put in over the roof timbers. Is this normal? There is only a small part of the vent that is showing each side of the roof timbers. Should I have them removed?

over the battens or the rafters?