"I'm so proud of all we've achieved together over the past six years: winning medals at world championships and the Paralympics, helping some extremely talented archers emerge and be successful at international level, and I've been privileged to work with some wonderful people.
"But I live in South Wales, and I spend far too long away from home, and after a lot of thought, I have decided that I want to have more time with my family.
"I've done two Paralympic Games cycles, and going forward the job is going to be more intense, with more time needed to dedicate to it, and I just cannot, in all honesty, commit myself to that.
"But I've no regrets, I've enjoyed second of the past six years, and in good times and bad, I have always loved my job and been fully committed.
"Obviously the highs were the days when the squad won medals on the international stage - and it didn't get any better than an all GB final between Dani (Brown) and Mel (Clarke) at the recent Paralymics.
"I think that over the past six years GB Paralympians have set the standards for the rest of the world to follow, but as proved at the Games last month, the world has caught up, the margins are now much narrower, and to move forward will take a whole new approach and dedication."
Archery GB has already begun the search for Tim's replacement, with senior management acknowledging he will be a hard act to follow.
"Tim's done a fantastic job, and losing him is a massive blow," said Archery GB Performance Director Sara Symington.
"I totally understand his reasons for stepping aside, but he will leave with everyone's very best wishes, our total respect, and our gratitude for all he has done, and achieved, for Paralympic archery in this country."
Said Archery GB chairman David Harrison: "Tim is an absolutely top bloke, but not only that, he is a fantastic archery coach, who cares passionately, and commands enormous respect among all those he works with, and also with other coaches and archers around the world.
"I'm really sorry that he's leaving Archery GB, but he goes with my very best wishes, and he can be extremely proud of all he's achieved during six very successful years."
Archery GB is sponsored by Foresters Friendly Society
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