World Jewish Relief holds many registration cards from when Jews arrived in the UK in the 1930s, and there is no charge for families to access these records.
Formerly called the Central British Fund (CBF), which is now World Jewish Relief, this organisation rescued around 65,000 people from Europe to the UK throughout the 1930s and 1940s. They were the charity through which 10,000 Kindertransport children found refuge, as well as being the main body to organise the rescue of the men to Kitchener camp.
WJR encourages families to apply online for records here: https://www.worldjewishrelief.org/about-us/your-family-history
And they have a page about the history of the organisation here: https://www.worldjewishrelief.org/about-us/history
Do get in touch – they’d love to hear from Kitchener descendants.
The National Archives online has a useful set of information for people trying to carry out family or historical research in this area: