You have plenty of time before creditors would start legal action and even if they did your IP can stop it anyway. However, if your creditors ring again tell them you are going bankrupt because your IVA was turned down. Tell them that you were trying to get something sorted with a new IP but since they keep harrassing you bankruptcy is now the only option.
This might keep them off your back for a bit while Melanie tries to get an answer from the dissenting creditor.