wait time for the I-485 interview will depend on the backlog at the local field office, so check the uscis processing time for I-485 for your local field office.
Also, i recommend having the employer extend the H1B if possible ,until you have the gc in hand. the moment you use AP or EAD your H1 status will end and you will have no status to fall back on in case GC gets denied. there is still a risk just in case marriage falls apart or other eligibility issues are discovered so general recommendation is to stay in status if possible till the AOS process is complete.