court bailiff to serve or not to serve

Husband has received the divorce petition and states that he left paper work with solicitor to deal with. As he said he would concent I said no need to go to solicitor but......
It has been 2 1/2 weeks now and the court has not receievd his acknowlegment. he states that his solicitor did say he was busy so it could take a few weeks for him to deal with it.
Does this sound right as i would of thought a solicitor would send the acknowledment back straight away as it is requested to be returned 7 days from posting.
If it is not returned will the ''case'' remain open indefinately or do I need to serve within a certain amount of time.
As this will cost me I am reluctant to jump the gun if the solicitor is going to return it at some point.

It is not unusual for it to take a month or more to return the D10, especially when a solicitor is involved. IT might take a week for your ex to get an initial meeting, then another week to review the forms, then another week of letters going back and forth. I would until at least a month has passed before going for a process server.