For GWR at least, it is looking at 175s to replace castle sets, with them being allocated to LA so they are at a dedicated depot to who can give the love, care and attention they need. But, it will take a lot longer than next August for that to happen. For starters, a unit would need to be released and sent to LA for fitter familisation, getting them cleared, then crew training for several depots between Penzance and Cardiff before they even appear. TfW 158s are out of the question, not likely to be available until late 2025/early 2026 for various reasons.