My first instinct was that it was an airfield that they hold one of the british aero nats at, but then you said east of cambridge.
The airfield i thought you meant is very similar. At this years nats, arriving aircraft landed in a westerly direction then continued to the end to a holding area. They then did a beautiful formation scarper to the pan (this happened when lots of ships arriving).
Perhaps my experience is very gash, having been raised on farmstrips and "less than controlled" airfields but i would have just said "Roger. Will expedite my taxi. " Then left the decision to him/her.
In my humble experience it is safe to land over the top of someone who is backtracking or is stationary if you keep them in view with sideslip, you know what you are doing and you have excess runway.
If they have to go-around and they feel agreeved then i am sure they will come and talk to you about it.
As an aside, a similar thing happened to me at work the other day in LGTS (look it up because i cant spell it). A C150 landed then could not decide where to taxi/back track/ spin on the spot etc etc. he was been actively encouraged vocally by ATC to leave in any direction possible but that did not nothing to stifle the surprise when he turned to face us and saw an A321 go around from the flare.
Were we cross? Of course not - it would make a good bar story for him.
Ps. dont get at 50' circuits until you have spent a lazy summer evening in your cub doing them, please.