I think you still get the one-time abatement even if earlier returns were late, as long as there was no penalty assessed.  But the prior-year returns should already be processed, which might not be the case if you are filing them at the same time.  

I don't know if the one-time abatement is automatic, or has to be called to IRS attention after the first notice.  And for a small amount, it might not be worth the effort.