@baz99...I had the same issue when I ordered my FE at the beginning of November because FE only available on MY19 config and dealer can only order new MY20 configs now. Some dealers have production slots for demos on MY19 FE pre-booked which they can allocate to customers and amend for you but most of them have already locked in their slots so they can't amend them anymore.
I was lucky my dealer could amend the config for me but another dealer I spoke to had already locked in their demo config and couldn't change it.
Great thing about getting the demo your dealer already has is you won't have to wait 3-4 months but maybe the spec is not perfect you? You can ring around the dealers to see if they can amend or have the FE spec you want already on order/in showroom or checkout autotrader like @MEO says or build an MY20 HSE to match the FE.