Got the wrong settings, how can I fix things?

I'm having a little challenge with settings on a project I'm working on in FCP 7.

I'm editing material I shot on a tablet a couple of years ago. When I began I created the correct settings. I'd transcoded the footage to ProRes HQ so ended up with Sequence Settings of:

Frame Size 1280 X 720, Aspect Ratio HDTV 720p (16:9), Editing Timebase 29.97

If I recall, though the Aspect Ratio says HDTV the important part was that it said 720p and 16:9. These settings match the descriptions of the media in the Browser.

My main Audio/Video Settings reflected this. There Sequence Preset was set at:

Apple ProRes 422 (HQ) 1280 X 720 30p 48kHz

(The info below the preset confirmed that this was correct, saying “ Use this preset when editing with Apple ProRes 422 (HQ) 1280 X 720p 29.97 fps material”.)

Somehow sometime recently when I went back to do a little work on this project the settings got changed. When I checked the Sequence Settings they had become:

1440 X 1080, Aspect Ratio HD (1440 X 1080) (16:9)

I had been working on some HDV material recently so suspect that's how this happened. Also, when I checked the main Audio/Video Settings I saw that they were as they had been before.

So my question is this: How, if I can, can I take the sequence I have created most recently and apply the correct settings to it? (The footage as it exists now has lost considerable resolution etc.)

I know sequence settings can't be changed once a sequence is created but is there any way to copy the sequence edit and past it into a new project and sequence with the correct settings. I've tried this but the material ends up enlarged and useless, but maybe I'm doing something wrong.

I've never exported an EDL but was wondering if one can do that within FC.

Thanks

John