The search of a landfill site for missing RAF serviceman Corrie Mckeague is expected to end by Christmas.
Police believe Mr Mckeague, who vanished on a night out in Bury St Edmunds, Suffolk, climbed into a waste bin and was taken away by a bin lorry.
The search of a site at Milton, Cambridgeshire, restarted in October after a search there ended earlier in the year.
Suffolk Police confirmed they expected the search to end by mid-December.
In a post on Facebook, Mr McKeague's mother said: "We are now about to start week seven of this search.
"Although things can change, and that's understandable, it is guessed that this search will be finished in the next two weeks.
"A further week will then ensure they have definitely exceeded the search area."
She said she was "incredibly grateful" police continued to look at the landfill site, which she described as "the most logical explanation for what has happened to Corrie".
Referring to her meetings with police, she added: "I also believe there are other lines of inquiry that have not been investigated, exhausted or ruled out yet.
"We have now been assured that every single one of those questions will be answered. That's what I've been fighting for."
Mr Mckeague, a gunner based at RAF Honington, was from Dunfermline, Fife, and aged 23 when he disappeared.
He was last seen on CCTV in Bury St Edmunds in the early hours of Saturday 24 September 2016.
The excavation has been focused on an area called Cell 22, next to the site of the original search, which ended in July after 20 weeks.
At the time, Mr Mckeague's family said they were "devastated" by the decision to stop the search.
It had looked into the Suffolk investigation and found no other possible lines of inquiry.