In fairness, you do not need to be using peak slots on an EDI-based aircraft to fly an early morning departure to Krakow at 06:40 on Mon/Wed/Fri, Lisbon at 06:20 Tue/Thu, Seville on Monday mornings and Thursday afternoons (peak business travel times) or Copenhagen (a route bloodbath) on Monday at 07:15. Shovelling any or all of these services to off-peak times and perhaps relocating the Berlin and/or Geneva services off EDI aircraft onto TXL or GVA-based aircraft could easily create the gaps required for a business schedule on EDI-BHX within the existing eight aircraft. I would guess that the delay in announcing a schedule is due to awaiting confirmation of requested slot moves for other services to slot coordinated airports, which will only become apparent in the next few days as airlines receive the output of their slot requests for S20. I might be totally wrong, but that's the conclusion I get to.