Birch coppicing

[Dermot]

Hi there,
Do you or your members have any experience with coppicing downy birch (Betula Pubescans)?
When the best time to coppice is and what height to cut the tree back to encourage maximum bud development? The plantation of birch is currently 3 growing seasons old and has an average basal diameter of about 2". We were planning to cut back sometime in winter 2021/22.
Thank you