I am pretty sure that there is no duplication on BHX-DUS. It is only served by BACON at the moment.
An indication might be that STR and FRA will loose their nightstopping aircraft. Particularly interesting in FRA's case as slots there during peak times come at a premium and surrendering them is quite surprising (unless Flybe intens to cash in on them - or maybe they are not included in the deal to allow BA mainline to nightstop an additional airframe at FRA).