Described as a 'stunning example of 1960s coordinated transport planning', the building has already been turned down for listing and now the search for an architect to design its replacement is drawing to a close.
Lancashire County Council has confirmed it has received 18 applications from practices wanting to draw up plans for a new bus station - a key feature of Terry Farrell's masterplan to regenerate Preston's city centre.
Designed by Keith Ingham and Charles Wilson of BDP, alongside the council's own engineer EH Stazicker, the existing bus station was opened in 1969 and is constructed from reinforced and pre-cast concrete.
However, the popular five-storey interchange will be bulldozed under the current proposals, led by Grosvenor Estates.
Though the building is showing signs of age, many of its supporters - including members of campaign group SOBS (Save Our Bus Station) - think the bus station could still be reused.
Nevertheless, Eddy Rhead, secretary of the 20th Century Society's North West branch, is becoming increasingly worried about the bus station's long-term future.
He said: 'There has been no new architectural evidence unearthed that will help save the building. It is still under threat.'
He added: 'You never know there may be a last minute change of heart and the perfectly good facility could be incorporated into the new scheme.
'I'm not hopeful though,' he added.
The architect charged with designing the new bus station will be announced in January.