Colony 20 was caught on William Lucy Way in Jericho part of Oxford. The swarm was confusing and disorganised. It took 3 visits to catch it.
The reason emerged why it was so hard to catch: the swarm had fallen off the tree and only part of the swarm joined her when she reformed at the top. I appear to have caught most of the rest.
The colony was merged when it became clear that it was queenless