Heavily indebted housing constructor Barratt Developments is concerned that the UK postal strike may dampen the response to its £720m rights issue.The company has issued a statement urging non-CREST shareholders intending to take up their rights issue allocation not to leave it to the last minute to do so, unless they intend using a courier service to deliver their application.‘Shareholders are advised to check the Royal Mail web site for an update on the status and impact of the industrial action before deciding how to return Provisional Allotment Letters and cheques or banker’s drafts,’ a company statement said.Helpfully, the company suggests shareholders seeking an alternative to the Royal Mail should consult their local business directories or search for local couriers via a search engine on the Internet.The deadline for shareholders to take up their rights is 11:00am on 3 November 2009.The rights issue has been underwritten so the company will not lose out if it receives a poor response to the rights issue, but a substantial number of shares left unsubscribed could cause a short-term stock overhang in the market.