Earlier this year the UK Government published an amendment to the UK Air Navigation Order 2016. The official updated document can be found here and is called the Air Navigation (Amendment) Order 2019. These changes are, in the most part, a direct response from the CAA to the drone related incidents at Heathrow and Gatwick over the Christmas period in 2018 that had such an effect on the UK.
The most significant change is the introduction of Flight Restriction Zones (FRZ). In the vast majority of cases the FRZ primarily consists of two separate zones. These zones are as follows;
You must not fly a small unmanned aircraft within the Flight Restriction Zone of a protected aerodrome without first ensuring that you have permission to do so. The Flight Restriction Zone is active at all times and applies to all small unmanned aircraft of any mass (even very small "toys").
There have also been several exemptions published that may affect you and as such you should be aware of:
Firstly prior to these changes' drones with a mass greater than 7kg operating within class D or E airspace outside of a Flight Restriction Zone would have required a non-standard flight (NSF) approval, however this exemption E4854 means that holders of a PfCO will no longer require an NSF for such a flight. This exemption is only relevant to operators with a PfCO, hobbyists will still require an NSF.
Secondly a competent observer can be used to maintain visual line of site if communication is ongoing between the pilot and the observer. The competent observer must be;
It is the pilot's responsibility to ensure;
This exemption (E4857) is only valid for operators with a PfCO.
More Information can be found on these changes can be found here