Help with mpeg2 export settings

I'm exporting a TVC and could use a hand with this if someone is in the know! I have a spec sheet from Adstream (the ad delivery agency) but just need to know how to set up the mpeg2 export GOP settings. This is the spec from the PDF

Video:

• 625/50 PAL

• 15+ Mbps CBR Long GOP

• GOP size: 12 (IBBPIBBP…)

• Profile: 422P@ML

• Colour Sampling: 4:2:2

• Field: Upper field first (odd) – preferred

• Video Size: 720 x 576 (608 inc. VBI) or 1024 x 576 (PAL)

• FPS: 25

Audio:

• Codec: MPEG Audio Layer-­2

• Channels: stereo

• Bitrate: 384kbps

• Sample rate:48khz

1. Premiere has the options for N frames, M frames, and closed GOP. How can I set this up so that I'm getting GOP size 12 and IBBPIBBP?

2. If my exported file is 720x576 25fps, upper field first, am I good to go? I don't understand what "608 inc. VBI" is referring to.

Thanks for any help you can offer, this is the first time I've edited something for TV and don't want to get it wrong