There is an instruction to delay installation of some topside LE wing rivets on Page 144 of the EX2 Wing Manual

"Do not install the first rivet in the #1, #3 and #5 rib at this time." (Page144)

When do these remaining HDW-SS/SS42D rivets get installed?

There is instructions about remaining rivets on Pages 150 and 152, are these related to the above?

There appears to be no reason to delay beyond the fabric covering stage.