The 669 families living in Blocks 74 to 80 at Commonwealth Drive were notified in August 2008 that they had to eventually move to new homes nearby.
The seven blocks had been identified for redevelopment under the Selective En bloc Redevelopment Scheme (Sers).
Under the scheme, which was introduced 20 years ago to rejuvenate older estates, the displaced residents would be offered new flats near their former homes at subsidised prices.
Five years after the initial notice, all but one resident had moved out.
The last one standing, Madam Foong Chea Tai, 67, who owns a three-room flat on the third storey at Block 79, said: "I'm not being weird, I just want to stay here."
She told Shin Min Daily News: "I don't want to move out. Now it's hard to buy a new flat. The lease is not up yet, I can still continue living here."
Most of the former residents in Madam Foong's estate are now living across the road in Blocks 50 to 53 after moving out about 16 months ago.
The units in the four 40-storey blocks, which were ready in July 2013, were offered to them by HDB as options to replace their old homes under the scheme.
After their departure, Madam Foong was the only person left living in the deserted estate.
The lifts in her block stopped operating. However, water and electricity was still supplied to her home.
The staircases in the other six blocks were gated up and locked to prevent access into the buildings.
The New Paper understands that Madam Foong's sons would visit her occasionally during her solitary stay there.
On Wednesday, Shin Min Daily News reported that 10 HDB officers, accompanied by police officers, went to Madam Foong's unit at 7.30am that morning.
The report said the policemen had protective shields as they stood guard on the third storey. It did not say why the police needed protective shields.
TNP understands that the visit was yet another attempt to convince Madam Foong to leave, but she refused.
When TNP went to her block on Wednesday afternoon, the three staircases leading to the units were gated and locked.
Responding to TNP's queries, an HDB spokesman said in an e-mail reply on Wednesday evening that Madam Foong had vacated the flat that afternoon.
It did not provide details on Madam Foong's departure but said it would provide her with temporary accommodation and help her with her housing options, including the purchase of a new replacement flat.
"At the request of Madam Foong's next-of-kin, HDB has got ready the keys of suitable replacement flats," the spokesman added.
"If she is willing to take up a replacement flat and sign the documents for the purchase, we will arrange for the keys to be issued to her immediately."
Under Sers, residents will receive market compensation for their HDB flats based on a professional valuation.
The spokesman said the compensation for Madam Foong's flat was based on its prevailing market value as at Aug 8, 2008, when Sers was announced for the area.
"With the Sers compensation and price discount, Madam Foong is eligible to purchase an equivalent new three-room replacement flat without any cash outlay. She will also have cash proceeds after the purchase."