There is no time for Cameron to get any treaty change from the EU.
Without treaty change there is no change worth the name - it can all change back again whenever the EU commission simply decide to change it.
So the battle lines are drawn right now.
In with the current treaties - including the hated Constitution/Lisbon Treaty.
In light of this, anyone who isn't already signed up for 'out' cannot be trusted in the out campaign.
This is a reflection of the debasing of EUphile and EUsceptic - especially by the BBC - now an EUphile is 'In regardless', EUsceptic is 'In but could be improved'.
They have no word for anyone who thinks the UK should rule itself.