I have just returned from the Cherhill and Yatesbury Parish Council meeting that included a presentation from Andrew Townsend of Andrew Townsend Architects and the National Trust.
My understanding is as follows:
There will be trial work over the summer, which will include using one or more different stone types (likely from the Bath area). These will be left over winter to assess how well this has worked.
After trial works have been assessed and costs better understood, the work will go out to tender and to Wiltshire Council for statutory consent.
It is expected that the main body works will be completed by rope access and scaffolding. This will include pinning, some replacement, and repointing the whole body of the monument.
Work this year will include the upgrade of the lightning conductor, which will include the digging of a trench, for which an archaeologist will be present.
No timescale was given for completion, have been given. However, when asked directly, the National Trust representation was definitive in his response that the National Trust will fully fund the complete works to restore the monument.
Photos of the presentation slides and one of mine to highlight some of the problem.
(While the National Trust were definitive in their response - I'm sure we will all be waiting with bated breath for the first sign of a you turn in their position).