Varies by species and between specific clones of the same species. Also varies with the temperatures you are growing at. SO there is no 'magic number'. That said, for me in my intermediate conditions, charlesworthii takes from 12 to 14 months to go to fully ripe, dry seed. Personally I prefer dry seed, as one is less likely to have transmission of viruses. Yes, I know no viruses have been identified for Paphs, but that is a limitation of testing, it doesn't mean they don't exists at all in Paphs. I started using dry seed for Phrags, because viruses are a problem, especially when breeding with old clones that have been around for half a century or more. End result, even though there are more problems for the lab using dry seed, I prefer it. I might not get the highest yeild possible, nor the shortest germination times from dry seed, but having 'clean seedlings' is more important to me.
Green pod harvest is usually somewhere around 2/3 of the time to dry seed, though you should check with more experienced hybridizers. Perhaps they will chime in. With good lab technique, virus transmission risks can be minimized with green pods, the better labs really don't have much trouble.