Duncan ...
Just to add a bit more background detail that might be of interest to you ...
Eastbourne is situated within UK Mil Low Flying Area 18 (LFA18), as shown on the following Map.
As you probably know the airspace in this neck of the woods is a bit intense given the proximity of the London TMA and the Gatwick CTA. You didn't mention the direction of travel of the Tornado or Herc ... but typically FJ traffic routes into LFA18 from North Kent skirting the TMA/CTA with a waypoint on Heathfield (
) then heading westerly for LFA1 staying well below 2,500'.
The Town of Heathfield is on high ground with a number of good visual Nav Check Points ... the most prominent being the TV mast which is 1007' AMSL. On the following map I have highlighted Heathfield and the A27 location you mentioned ... again that particular road/rail feature is a good visual Nav Check Point. The viz wasn't too good yesterday so I doubt Heathfield would have been a desirable waypoint because of the TV mast obstruction/hazard.
Sadly we don't get too much UK Mil (RAF) traffic ... although ... as you probably know ... RAF Odiham Chinooks are frequent visitors by day and night. Occasionally the French lob round low level in their Transall C-160's.
10/15 years ago, when RAF Bentwaters was open, USAF A-10's were regular visitors.
In terms of actual activity in LFA18 we are way down the batting order (stats for 2010-2011)
I'd love to meet the 193 complainants
More MOD background information here ... It was possible to look up on the former MOD Website if there were exercises/ops in particular LFA's ... but that seems to have been dropped in favour of the UK Gov Website which appears more geared up to "inviting" complaints than explaining the need for low level flying training
MOD Mil Low Flying Statistics 2010-2011
UK Government Mil Low Flying
I had to laugh when I looked up the UK Gov URL as Mil Low Flying comes under
Noise, Neighbours, Pets and Pests
Hope this has been of help/interest ...
Best
Coff.