The seams do work a little as the aluminum expands and contracts so, yes, eventually you may need to reseal the seams. It is annoying but simple: tape off both sides of the seam with blue painter's tape, apply the sealant, smooth, remove tape.
Old (usually dirty) Nissan Titan
Old (enhanced with "male pattern baldness") Sovereign
Young, lovely bride
Goofy dog, dismissive cat