Orient supporter Matt Porter has expressed sadness at stepping down as chief executive but insists the change of ownership has given the club the chance to move to the next level.
Porter worked his way up from the club's press officer to chief executive and has overseen significant progress during his eight years in the role.
Francesco Becchetti completed his takeover of the O's on Monday when Porter's departure was confirmed. It was never going to be easy for the lifelong fan to relinquish the position but Porter is adamant that it is the right decision.
The outgoing chief executive said: "It's been a labour of love as a boyhood fan and then moving up to chief executive. It's been 22 years since I started going to games and I've seen and done most things here. It's a big day and I always knew that it would come at some point.
"It's sad to be leaving the position but the club needs to keep moving forward. I'm very proud of what we've achieved here and I don't think you could have dreamt of some of the things we've achieved both on and off the pitch."
Porter continued: "My employment is with the chairman and not the football club. It's also only right that the new owner needs to put in place his own team. But I will remain on the board and will be here to help. I have knowledge of the club which could help with the transition to the new owners and will still go to games as a fan."
There have been plenty of highlights during Porter's tenure with the O's including last season's record breaking campaign which saw them agonisingly miss out on promotion at Wembley.
Porter said: "The highlight was promotion at Oxford in 2006. The Arsenal home game also stands out while there is so much pride from the last 12 months. I would not have changed a thing and we were just phenomenally unlucky to fall at the final hurdle."
When Porter became the youngest chief executive in the country in 2006 at the age of 26, the O's were on their way to promotion and he has overseen their progress to an established League 1 team. But he believes the additional investment from Becchetti can provide the club with the resources to reach the Championship.
Porter, who was recently elected on to the Football League board, said: "Our target was to stabilise as a League 1 club which we have done. We increased attendances and our fan base, have developed the academy and overseen the stadium redevelopment. We got so near to the ultimate goal of reaching the Championship but hopefully the new owner can provide that extra few per cent to take the club to the next level.
"He [Becchetti] is extremely wealthy and ambitious. He went to Wembley [for the play-off final] and would have loved the club to have got promotion but the first step now is to get to the Championship.
"This is an exciting time for the club and is a real chance to move to the next level with the added investment."
Some fans are understandably concerned about the takeover particularly with such a mixed track record of success in foreign investment across the country. But Porter believes Italian businessman Becchetti, who has moved his family over to London, has demonstrated his suitability during their recent meetings and significantly has bought into the importance of continuity which has served the O's so well in recent years.
He said: "Anything unknown always causes a bit of apprehension but from the meetings we've had he has been both sensible and ambitious. But he also recognised the stability and progress we have made and how this has led to our success.
"They have been very impressed with Russell Slade and there are meetings planned for this week. His football advisers and the manager all seem to be on the same page."
Porter, who will remain as a director at Orient, will continue to work for Hearn as the chief executive of the Professional Darts Corporation. He insists the sports promoter deserves to be held in high regard for the way in which the club has been run and the position it is in following the takeover.
Porter said: "I couldn't have wished for anyone better to work with. Everyone at Orient is indebted to Barry because the club is very stable and has solid foundations which is in stark contrast to when he took over."
He also thanked the club's fans for supporting him throughout his time at Brisbane Road.
Porter said: "I was 26 when I got the role and I wasn't the typical CEO but the fans backed me and I couldn't have done the job without that support so I'm very grateful. I always tried to be honest even if it wasn't the things people wanted to hear."