"Hard binding and light blue cover" is almost surely a Scott "Junior" International album which was hardbound but had paper glued onto the boards of the covers. The same album also came in a dark blue cover without the paper on the covers, a bit heavier duty I imagine but a little more money to buy. Because so many were apparently sold, those albums, often in good shape, can still be found today on places like
ebay.
As for the other (less "Junior") Scott International albums, they most commonly came in brown covers (hence their nickname of the "Browns") but they also existed back in the 19th century in other covers, as well. These were Scott's comprehensive world albums with a space for every stamp issued while the Junior album was for "representative" stamps only and was more for younger collectors or those without deep pockets. Eventually, there were four volumes of this album, one for the 19th century, one covering 1900-20, one for the decade of the 1920s, and the final one for the remaining years up to (about) 1940. That was about the point when Scott moved their comprehensive "brown" albums over into the Specialty series of country and regional albums, abandoning the browns in favor of the "Junior" album becoming their new worldwide album from that point on.
There were other volumes of the comprehensive album with different dates (your guy mentions "1928-32") along the way as Scott did not want to wait ten or more years before issuing the next volume, so Scott updated the album by publishing what turned out eventually to be interim volumes. I've even seen a few updates for a single year, more like supplements than new volumes, but published in book form.