Originally Posted by
Sandy Boots
I have noticed that on certain days there are two BA174 flights into LHR from JFK usually following each other.
I think you are mistaken.
Airlines don't schedule two flights on the same day with the same flight number, for obvious reasons. Very occasionally you will see two arrivals at an airport on the same day, but invariably that's because one is the delayed flight from the previous day (for example there were two BA232 arrivals from Moscow last Sunday, one being the Saturday flight). When this happens, the delayed flight will typically be given a different ATC callsign, usually involving either a suffix (in Sunday's case BAW232X) or an ad-hoc flight number in the BAW960_ range.
BA174 has operated more or less on schedule every day this month so far. The last time there were two BA174 arrivals on the same day was 4 years ago.