Treehouse/decl Planning Permission

[mulliners39]

I have recently built a deck 10m long by 3m wide and as it is on a slope,2m at the begiining and 4m at the end in height.
The idea was to put a treehouse on the deck but after my neighbour was all for it until she changed her mind(due to us objecting to a 4000 sq ft extension which would have overlooked us)
The deck sounds large and I guess it is but it is completely surrounded by hornbeam trees 60 ft high.Planning enforcement wewre called and the officer said he would try to keep a lid on it(which he has done) as I suspect he sympathised as the deck is all natural chesnut and completely hidden.

What do I do now-apply for planning and risk being told 'no-take it down'
Wait 4 years (1 year has passed) and finish off the deck with railings and sairs.

I live in the countryside,my neigbours could if they strained make out a little of the deck-its also an AONB area

Does the 4 year rule apply and could i consult without any risk in the planning dept?

[welsh brickie]

its a very grey area you can apply for planning claiming you have just found out that you may need planning and thought it best to consult the officer.
Or leave it,If you decide not to apply and finish it and there is a complaint they will make you take it down.
From personal experience I would consult the planning officer,be as polite as possible be open to all and any changes he may suggest,its best to keep him on your side and get the planning consent.