I have a 1.5 year old condo and I recently pulled the old caulk job the builder put in, and found they grouted between the tub and tiles and just caulked over it. The grout is discoloured in places ...
I am recaulking around the edge of the bathtub where the tub meets the tile on the wall. I got caulk listed as "for kitchen & bath": Loctite PL(Pro Line) 530. I haven't used the shower in weeks ...