Taking bees that have set up home in a hollow tree is rarely a one person job. There are a number of WBK members who are willing to carry out such work, but they are not always available.
Generally bees should only be removed between March and September/early October, but in an emergency they can be accessed at other times. If you have bees in a tree that is being felled or has fallen down, it is best to contact the swarm co-ordinator by email and he can then put you in touch with someone to discuss your situation in more detail. email@example.com
As such jobs are complicated and time consuming we generally ask for a donation of some sort to the division, although in return there is sometimes wild honey from the bees that we can give you. Here is a video of bees being removed from a tree to give you an indication of what is involved.