! I've been doing it for years!
If I have any left from last year by the time I harvest again, I let it sit out while I prepare the current crop, by that time the olive oil is again room temperature. I then pour what is left into a bowl, put the new cloves into the bottom of the jar (old pickle jar) put last years crop back in on the top and refill with olive oil, all done! The older cloves will become more infused with the oil the longer they are in the jar and become saturated almost translucent.
Sometimes the gloves will off gas and tiny air bubbles will be all over the oil, not a problem, the next time you use the gloves let it sit till room temp with lid off and just sir to release the gases.