Duck .... my advice would be to hold off reporting any kind of fault, that would mean an engineer attending site IF there is nothing wrong with your line. Believe me, if it's a 'Line tests ok' and the line is nice and quiet, the SP will be billed by us, and I'd put my house on it that they'd pass that charge on to you.
Playing Devils Advocate, the reason is, that nationwide,there must be thousands and thousands of wires routed through tree lines. Imagine the cost of replacing them just for the sheer hell of it ?. I concede that eventually fault conditions will arise, but as I say, if it's currently fault free I would leave well alone.
The 'legals' are a minefield by the way, Ive dealt with a few whilst in a covering role for my manager. We also now have 'Tree protection covers' (very tough, but flexible palstic) that we install on Dropwires wherever they come into contact with trees.
In a nutshell ...... save arguing with your neighbours, let us deal with that when the time comes to change your Dropwire. You'll also save yourself quite a bit of money as well (I think its around £55) for an engineering visit that won't alleviate you woes.
May not be what you want to hear Duck, but without splashing out cash, it's what will happen.