EASA regs are UK law, under the Withdrawal Act. After 31/12/2020 the UK is able to diverge on selected parts but the UK CAA is doing very little of that, presumably because they want to do a treaty with EASA for mutual paperwork recognition, so they don’t want to do “good stuff” because it would be provocative 
Lots of G-regs now have LED lamps.
Bathman wrote:
Does this apply to G reg aircraft as well?
I’m sorry but I don’t know that; will have to pass that question to anyone more familiar with this.
Only issue 3.0 applies to G-reg aircraft as it was published before 31/12/2020.
Not seen any sign that there is a UK issue 4.0 planned.
How did the G-regs install LED lamps?
Peter wrote:
How did the G-regs install LED lamps?
Whenever they are FAA or EASA approved installation was always possible. But you had to have the installation signed off.
“New” is that the pilot/owner may release to service any self-installed LED bulb.
Peter wrote:
EASA regs are UK law, under the Withdrawal Act.
Even changes after New Year 2021?
No, obviously.
“New” is that the pilot/owner may release to service any self-installed LED bulb.
What does this boil down to? You can buy a cheaper lamp?
I’d be careful, because all LED lamps of this type contain a switching power supply, which has a great potential for radiating stuff and affecting comms/nav.
UdoR wrote:
It’s a pity that position lights are not (yet) available for standard change.
They are. The same standard change (CS-SC031c) applies to position lights and anti-collision lights as well as taxi and landing lights.
Airborne_Again wrote:
applies to position lights and anti-collision lights
Sort of not. Look:
Quote Additionally, the following conditions apply:
— taxi and landing lights that are not combined with anti-collision lights or with position lights are
eligible for installation without an EASA Form 1;
— anti-collision lights and position lights for day VFR aircraft are eligible for installation without an
EASA Form 1; … /Quote
So I could install it, but the aircraft would be reduced to day VFR only. This means for me: not yet possible. For anyone only flying day VFR: yes, you can put these lights on.
Now, an interesting question would be: what if I was putting these lights on, whenever flying day VFR, what I’m doing most of the times anyhow. And whenever IFR is planned, I change bulbs. Or not.
Peter wrote:
What does this boil down to? You can buy a cheaper lamp?
You can buy cheaper lamps and / or you can sign it off yourself. So you can put in certified lamps but don’t need no release to service from no one but yourself.
