Peter Knatchbull-Hugesen, a Director of Arena Coventry Limited and Chairman of the Alan Higgs Trust has said that The Higgs Trust have heard nothing from SISU.
Coventry City's owners pulled the Academy out of the Alan Higgs Centre in April, following a row over £14,000 in rent and damage to property.
Speaking at the Sky Blue Trust's AGM, Mr Knatchbull-Hugesen said: "Getting hold of SISU has been difficult.
"Joy Seppala received a letter from the Alan Higgs Centre in April giving a deadline of June to reply. We have had no answer and deadline has passed.
"We have had to make other plans as the club have not replied and we have to think about how we take the business forward."
Steve Waggott has checked out the possibility of using the pitches at Warwick University and PKH said: "Warwick University does not have indoor training facilities for the academy to use in the winter Without indoor training- no category 2."
Speaking about the Ricoh Arena, PKH said: "As a charity we have to get independent valuations on anything we sell. This costs around 40k for the Ricoh.
"For the Bruce Springsteen gig, Arena Coventry Limited employed a thousand people on the night alone. This doesn't include anyone setting up the arena for the gig. "
Talking about the Sky Blues, who are still refusing to name their home venue for matches this season, he said; "A city without a football club is a sad thing. Arena Coventry Limited are talking to administrator several times a day", as well advising they are still in discussions with Preston Haskell IV and are aware of at several other sports clubs that want to play at the Ricoh Arena.
"If Coventry City Football Club Ltd is liquidated approximately £3-4m will be owed to Arena Coventry Limited."
Source: Coventry MAD