a couple of thoughts to consider:
With earnings on 9/18, the weeklies won't come into play for the earnings so I don't think there is a lot to do with them for a trade.
IV is high as you noted, but when you look at the IV charts for FDX it doesn't always show a consistent pattern of the IV spike into earnings cycles so tying the IV strictly to the earnings event may not all there is to it.
With the thought that the options may be overpriced, maybe a DC with 105p and 110c (with the stock at 107.60) using the Sept and Oct monthlies may be a decent play. Once we're at the earnings date, you can consider if you want to leave something on through earnings given that FDX is not typically a big mover on earnings.