Let the critiquing begin with this. One toe over the line sounds like tow the line. If the editor is kind he might revise with his blue pencil, or if he has fifty more manuscripts to review before the ink truck arrives for the regular afternoon delivery he might simply use the self-addressed return envelope.
Yes, I believe it is ‘toe the line’ as in step up to the line and say you’re on our side.
Noted by Orwell.