Lon Info can of course activate your flight plan etc! (not so easy to do on Thames now not co-located with the LHR FBU)
Anyone been given the new squawk by LI (0027)?? Only seen it on screens once myself. Most important thing to remember is that they do not have a radar. Also it is not run by controllers but by senior assistants as the ERC at Swanwick who do a very good job.
With regards to Thames it very much depends on the workload. As I have said on here before, our good book says our area of responsibility is within the M25 - though everyone if able works tfc way past that! One thing to remember is that Southend are a LARS unit so you can always call them.
The traffic that amazes me is aircraft off Elstree - that call approaching the Lea Valley and routing out to Essex via LAM. Giving that LAM (Stapleford) is normally chocka with returns I will pass you to 122.8 almost straight away and then straight to Soufffend!
stay safe!