Some of Annie's friends also have kids that go through potty training, and actually succeed. even if he's regressed, Annie knows that Gus will get ready to move to undies on his own time, but sometimes her friends would give Annie the rest of their kid's pullup packs, as they won't need him anymore.
Gussy is still far from being ready, but letting him wear pullups once in a while, specially when they didn't paid anything for these, always brights Gussy's day. At least until he wets it.