TBH,neither you nor I know what Hornby is planning.
I'd be very surprised if they are about to release a new W/C or BOB as they have two versions of the current model scheduled for Summer release in 2023.
It could be that they will scrap these models and produce a "surprise all new loco" for next year in the new model range.
Bachmann for example, are one such company, who only announce a loco just before release.
Time will tell, but I don't think the wait will be too long before someone picks up the baton!