RFU Chief Executive John Steele was sacked in June after the organisation failed to appoint an elite performance director.
"Two years ago would have been harder because we may have been looking for some new players. But everything's in place in terms of our preparation. We're set up here,” Johnson told the Evening Standard.
"The last four weeks have just flown by. Next week is the last of our training camp and then we're into warm-up games. We're off in five weeks. We'll be on the plane before we know it. It is really far removed from the players, it doesn't affect them.”
England face Wales and Ireland in World Cup warm-up clashes in August.