720p 16:9 to SD for broadcast

[Matthew Bradshaw]

Hi. 720 by 576 is correct. If you are viewing it in a 4:3 frame then it should look squished, that is the anamorphic bit of FHA (Full Height Anamorphic). They will know what to do with it. Who are you supplying it to? I freelance for many broadcasters here in the UK and may be able to get you a name to talk to. Did they specify a codec?
You could ask them for a file and then use the function in compressor to drop a file into a new setting which copies the parameters. Here is a link to the itv delivery guidance doc. Page 19 gives you a visual idea of how squished it should look. https://www.itv.com/documents/pdf/Technical%20Requirements%20for%20Commercials%20Material%20Delivered%20to%20ITV.pdf
Good luck, Matt.