Not true. many aircraft do fly below 1000ft
Your GPS controlled model is classed as a "Small Unmanned Aircraft"
and no longer a Model Aircraft.
Lots of info in CAP722
http://www.caa.co.uk/docs/33/CAP722.PDFe.g.
"4.1 The aim of this policy statement is to clarify the position of the CAA in respect of its
role in assisting the UAS industry to find a solution to achieving a capability and level
of safety which is equivalent to the existing 'see and avoid' concept. It is also
recognised that Sense and Avoid is only one of a number of requirements that will
need to be addressed for safe operation of UAS.
5.1.2 The separation and collision avoidance capabilities must be able to:
• Detect and avoid traffic (air and ground operations) iaw Rules of the Air;
• Detect and avoid all airborne objects, including gliders, hang-gliders, paragliders,
microlights, balloons, parachutists etc;
• Avoid hazardous weather;
• Detect and avoid terrain and other obstacles;
• Perform equivalent functions, such as maintaining separation, spacing and
sequencing that would be done visually in a manned aircraft."
"NOTE 3: Further Constraints the CAA May Think Fit to Apply
Further constraints the CAA may think fit will normally include a prohibition
on flight:
a) at a distance beyond the direct unaided visual range of the pilot/operator
of the said aircraft and in any event at a distance exceeding 500 metres
from the pilot;
b) within a specified distance, normally 150 metres, of any congested area
of a city, town or settlement;
c) within a specified distance, normally 50 metres, of any person, vessel,
vehicle or structure not under the control of the aircraft operator except
that during the takeoff or landing an aircraft to which this subparagraph
applies shall not fly within 30 metres of any person other than the person
in charge of the said aircraft or a person in charge of any other small
aircraft or a person necessarily present in connection with the operation
of such an aircraft;
d) unless the aircraft is equipped with a mechanism that will cause the said
aircraft to land in the event of a failure of or disruption to any of its control
systems, including the radio link, and the person in charge of the said
aircraft has satisfied himself that such mechanism is in working order
before the aircraft commences its flight."
As you see it's a
Minefield 
, you would need a Lawyer to give a full answer
I'm in No way an expert on this, but I do see potential problems.
Thu May 07, 2015 8:15 am by 
light aircraft can only fly below 4000 feet when coming to land 
low flying military jet 
and i was flying it my sellf 
i think to be honist it should be quite good flying one 
well i have a paraglider in my house and that is massive its a full flying sorce i can sit on the seat and fly in the uk with no training and no help and there is no licence in the uk for that at all even a novice can fly it and any one brave enough to fly one can buy one and take it up and i think that must be much more of a problem for jets or aircraft and that is defintly f,p,v and by the way light aircraft fling lane is 4000 feet i know this because below 4000 feet is for power microlights and thing that go in to that catagrey
mom always told me if theres a will theres a way 
here it is ther own rulls and things to make you pay more out ,,,read i have my oun wing can i use it then it says as long as we say you can 
now thats what i dont like at all that red tape where it is not needed
