I was told you had to wait 1 year after the divorce was final. I started about 4 months prior to that year mark, everything was submitted about a month before...they went ahead & started processing it. I had my 1st decision by shortly after the 1year anniversary...still waiting for the 2nd :) any day now...tic toc, tic toc
What I have seen is the waiting period can vary from Tribunal to Tribunal and it can be changed. It also, I was told, has to do with how long the couple had lived apart/been estranged before the divorce was final. That time can go toward the waiting period.
It does seem to make sense that the Church would want to see if there will be a reconciliation; the waiting period could also be good to slow down the 'moving on process'. Rebounds, lack of adequate adjustment and grieving time....I think we see the Church, in her wisdom, trying to help us in the wisest way possible.