Thanks for the congrats.
Your dojo in London is connected to Veszprem?
We had a 4th Dan Sensei visit us last year from there. (Sensei Janos...forgot the last name right off hand.)
As for 4th kyu, earliest I can test would be Dec.
(Testing either in Szeged or Makko I believe - a good distance from where Im at.)
our dojo is connected to the Aikido Foundation in Hungary which is connected to Veszprem where the summer camps of the Foundation are held but, unfortunately, it is not connected (as far as I know) to the sensei who visited your dojo. (Google shows his name is Janos Veisz but their website says he's 3rd dan so I'm not 100% sure).
Sometimes things in aikido are complicated