I've seen quite a number of original ASM panels and pages from the 70s (my brother & other Romita collectors have a few of them), and I remember some surviving panels from Andru-illustrated Giant-Size Spider-Man #1 from 1974 ("Ship of Fiends" / "The Masque of the Black Death" with Dracula), ASM #127 ("The Dark Wings of Death!") #128 ("The Vulture Hangs High!"), and other issues having what were clear Romita layouts for certain character positions and angles, and other pages for the same page number with Andru's own breakdowns.

Their existence would lead one to assume this transitional period had Romita providing some guidance to maintain the visual consistency established in the Romita (and Kane) era of ASM. It certainly did not happen during all of Andru's run on the title (of the original pages I've seen), but early on, some Romita layouts were there.