Shaf, you've asked a question but obviously don't like the answers you're getting.

I would suggest that, if you're charging for a wedding, the couple should have the video by the time they get back from the honeymoon. Certainly a professional video should be ready no later than two weeks after the ceremony.

Excuses are not acceptable. You are being paid to provide a service and you should deliver on time. If you film on a Saturday, have Sunday off, you have the whole week, Monday to Friday, to edit the footage, ready for the next wedding the following weekend. If you don't have a wedding the following Saturday, it doesn't matter, you must still edit your footage immediately since the paying customer is waiting to see the results.

Anything longer and the customer is entitled to withhold part of the payment.

If you join an organisation like the Institute of Videographers, they will be able to supply you with details of court cases where the customer took the videographer to court (or vice versa) and the court has upheld that a wedding video has to be delivered within a reasonable time. A month is not reasonable and three months is totally unacceptable.