How to downgrade?

[sports_brah]

I've got a rolling contract sim which costs me £12 for 1200 mins, unlimited texts and 1gb data with blackberry.

I'm moving countries fairly soon, and thus won't be using the phone. However I still want to keep it for random texts which could be important.

How would I go about downgrading it to something I don't pay monthly for? Can I use the same sim card?

Thanks

(I'm with Virgin mobile)

 

[dasyad]

Switch on to pay as you go?

 

[Hyburnate]

Phone Virgin.