There is a Romney Marsh luncheon circular trip headed by Tornado today. Coming up from Southampton to Ashford then Rye, Hastings, Tunbridge Wells, Tonbridge, etc. Times on the UK Steam link below.
The Dover luncheon circular trip on 22nd looks at the moment as though it will be headed by Black Five 44932. A couple of good vantage points are the island platform at Dover Priory or the footbridge over the line just before the Shakespeare Tunnels, accessed from Aycliffe. Get there in good time as I missed the last one which passed through several minutes early. Times will eventually be on the UK Steam link below but may not appear until the last minute as they are the preserve of Network Rail.
http://www.uksteam.info/tours/trs10.htm