URGENT: advice on admin/writing job - help!!

nzmegs

I am going to have a phone meeting with someone who is considering me for a position in a couple of hours. The role is project managing a group of writers. Giving them instructions, receiving the articles, proofreading them and passing them back to clients.
I am a freelance writer, with experience in general virtual admin. But i am a bit scared about this role. it will take up quite a bit of time (around 2-4 hours a day) and I currently have long standing clients who take up 3-4 hours a day.
it is freelance - so what should i charge? I have estimated around £15 an hour at this stage. But I would be willing to offer a rate per block of 10 articles which I would put at around £30-£40.I can proof read 10 500wd articles in around 2 hours.
Does anyone else have experience of this? the proof reading part will be easy but all the dealing with people might take up more time than i think. Eek. it is scary.
I only started as a full time (part time really) writer a year ago and this will double my income in one go.

is this a good opportunity and am I underselling myself? i need a confidence boost quick!

Googlewhacker

Does that mean if you do this work you will effectively be working a normal week, if it is why not give it a go. Just make sure you are organised and the worst that happens is you can't do it. It is better to try and fail than not try at all.