Can a form be 'closed' the information retained and the same form be reused?

Can a form be 'closed' the information retained and the same form be reused?

Hi

I have a problem that I am hoping someone can help me with. I'll try to explain my issue as clearly as possible.
  1. I want staff to be able to mark what days they can work in the upcoming week
  2. I have a form that does this - it has the week days that they can work
But then I hit logistic problems.
  1. I normally ask them on a Wednesday to fill in the form for next week.
  2. This means that Thursday and Friday's data for the current week gets wiped and replaced with next weeks data.  
What I need is to be able to close the form, retain the data and open a the same form to get next weeks replies. I thought about doing this as a subform, as you can keep adding rows, but I am sure that there is a better way of doing it.
I have also thought about having two forms, week a and week b, but this could get complicated with people using the wrong form. 

Can anyone help me with this?