First Virgin flight to Vegas

Hi all
I have been an avid viewer of the forum in the past few weeks,
I have been lucky enough to win a 4 day trip to Vegas and have a few questions that you may be able to help with?
We are flying as part of a very large group and have been told that we will be issued tckets a couple of weeks prior to the flight, as we are in such a large group will this preclude us from using OLCI?
Will I be able to pay for extra leg room seats if the fancy takes me?
Will we be able to check in the day prior as we are close to Gatwick
Lastly, my wife is allergic to yeast so do you have any suggestions for meal choices and special requests? From what I can tell there is a meal service not long after take off and another near landing, are there snacks ect available
Thanks for reading and helping
I have been an avid viewer of the forum in the past few weeks,
I have been lucky enough to win a 4 day trip to Vegas and have a few questions that you may be able to help with?
We are flying as part of a very large group and have been told that we will be issued tckets a couple of weeks prior to the flight, as we are in such a large group will this preclude us from using OLCI?
Will I be able to pay for extra leg room seats if the fancy takes me?
Will we be able to check in the day prior as we are close to Gatwick
Lastly, my wife is allergic to yeast so do you have any suggestions for meal choices and special requests? From what I can tell there is a meal service not long after take off and another near landing, are there snacks ect available
Thanks for reading and helping