The Candystripes play their last home game of the season on Friday when they host Sligo Rovers.
However, the club still do not know when work on a multi-million pound redevelopment of their stadium will begin.
Derry City and Strabane District Council, who own the stadium, said a tendering process is ongoing.
Club chairman Philip O'Doherty said he is concerned that Friday's game could be the club's last at Brandywell for some time.
"The ideal situation would have been that, after this last home game, the diggers would be in the next day," Mr O'Doherty said.
"That's not going to happen, the longer construction work is delayed the less games we will play at Brandywell next season.
"That means that the possibility of having the European tie at Brandywell is basically under threat at the minute," he added.
Derry City secured their place in next season's Europa League competition with last week's 2-1 victory over Bohemians.
Brandywell 2016 Timeline
Earlier this year, Derry City sought out venues for the relocation of six home games which would be affected by the redevelopment.
Since then, the Brandywell delays have left talks with other clubs 'up in the air', Mr O'Doherty said.
"We have no clarity from Derry City and Strabane council which is extremely frustrating.
"The club has been slaughtered on social media about holding things back but I do not know when this project will start.
"Derry City Football Club is also a business and it is not a good situation for the club to be in."
A spokesperson for Derry City and Strabane District Council said: "The tender process for the appointment of a contractor for the Brandywell Stadium redevelopment and dog track is ongoing.
"Council is hopeful that these processes will be concluded shortly," they added.
Although Friday's tie with Sligo Rovers is the last home game for Derry City, other stakeholders at Brandywell - which include a greyhound track - have use of the stadium until at least the end of November.
That means construction could be delayed further.
The chairman of Derry City Football Club has warned that European football at Brandywell stadium is under threat.