No police support for this one, no action taken on the march complaint ..... First off seek to have it thrown out as per Rod's advice. If for some reason the mag looks likely to allow it, you can then offer an undertaking... No direct legal consequences for a breach, but is a 'promise' to the court NOT to breach .... Just means that if there IS a breach contrary to whatever conditions are on it, there is a VERY high chance that an interim IVO will follow.
A joint undertaking just means you both give that undertaking