Ignoring xl5 rantings, most operators EXCEPT UK airlines keep the FD visible during approach. I have flown a few UK configured aircraft (on short-term leases) and on those the FD bars disappeared at 1500ft RA (initially we thought something was wrong, the first time we saw it!). Apparently has to do with required monitoring of raw ILS data during approach. On other a/c the FD bars remain visible throughout. Identical setup on 757/767s.