I kind of answered this to you in another thread, but like most people, I've never been able to get most EO's to stick. Even with trying the anchoring methods lsg explained above. For me trying to anchor them with litsea and bergamot, just makes the soap eventually smell like litsea and bergamot. The initial EO scent fades.
I have had good luck with Lime EO, Bergamot, Lemongrass, Litsea, and that's about it. The rest seem to fade within 3 months or sooner.
I do have a lime bar I kept for myself from a couple years ago, and the scent is still there. It's not strong like it was, but I can still smell it.
I'd rather spend my money on FO's and not bother with fading expensive EO's anymore.