The phrase 'timescale for when' is correct and usable in written English.
It is often used to indicate a timeline for when something is expected to occur. For example, "Please provide a timescale for when the project should be completed."
Provide a timescale for when the Pip will be reviewed, and how often.
What is the timescale for when drones become part of business and society's everyday life?
Moreau did not give a timescale for when such insurance might be available in the UK and said the company was looking at how best to develop it.
Rolls added: "As the investigations are still ongoing we are unable to give any further details or a timescale for when they will conclude".
The report does not give a timescale for when article 50 would be triggered but David Cameron has suggested it would be straight away.
Sinofsky declined to give a timescale for when the next release of Windows will be available, but said that 24-36 monthss between releases seems about right". Windows 7 was released in October 2009, suggesting that the release will come between October 2011 and 2012.
The amount the government spends on back office software (that used for shared services, such as HR and payroll) will be reduced as it will now be able to set its own timescales for when upgrades occur.
"I'm not going to give you a timescale of when he's going to be out but he'll be out for a few months rather than weeks.
The "comprehensive, independent investigation" will be carried out by one of the big four accountancy firms, although no timescale has been given for when it might be completed.
No timescale has been given for when the film would go into production.
No timescale has been suggested for when Trott, who scored 19 runs in two innings during England's 381-run first Test defeat in Brisbane, will play cricket again.
