It just means after running it that you should go back and make sure they are all still 55ft lbs. Re-torque just means check them again.
The link that Gary WA provided makes a lot of sense, being new to Model A's I have no clue as to what a Brumfield head is. Does this procedure look good for a standard head?
John
This^^^ After a new head gasket and leak test the nuts were down to 35#.Check them often until they hold 55. The torque will decline.