The email continues that UK employees “need to be mindful of the hours they work and are asked to have 11 hours outside of work in each 24-hour period.”

This is an attempt to stay within working time regulations in the UK but they are violating this bit

By law (The Working Time Regulations 1998), employees and workers have the right to the following rest: …. between working weeks – 24 hours every 7 working days or 48 hours every 14 working days

By having a 19 day unbroken run which, as I understand it, is not legal.