Premium Reward Upgrade x2 clarification

Hi

On my Virgin Atlantic Reward statement I can see the following

[*]Premium Reward Upgrade x2

Does it mean a Premium Reward Upgrade for 2 return flights or is it for two flights (1 return / 2 singles) ?

Any clarification appreciated

2 returns

Oh really ?

So myself and my wife could use them for two return flight upgrades s or I guess we could take the children (two kids) and use them for 4 one-way upgrades ?