According to the statement on the VOC website, £1m, not 250k, is required bt the end of the month in order to continue the project.
http://www.tvoc.co.uk/index2.php
The XH558 Club also quotes Dr Pleming as saying that the running costs will be £1.2m per year.
http://www.vulcan558club.com/AGM_Min..._Questions.doc
So for the quoted 15-year timespan of the project, with inflation, well over £20m will be required.
If these figures are correct, then £1.2m to get it to its first airshow next season, then another £1.2m for a season's operating costs means that £2.4m of this (plus funding for the next set of 'unforseen overuns') will be needed by September next year!!!!!