Corriere della Sera explains that there are ongoing discussions to avoid tensions between the regions:
After protests and controversies over the possibility that the seven-day postponement affects only Lombardy and Piedmont, mediation is being sought with the Southern Regions that threaten to allow only those who present with the serological test carried out in the previous three days to enter their territory .
The certainty on what to do will only come with the weekly monitoring data, which will arrive today.
The government line is to move all together. So – unless there is a surge in new positives in Lombardy or other regions – it will be proposed to confirm free circulation from Wednesday. And if some governors were to express fears regarding arrivals in view of the holidays, containment measures will be proposed that can still reassure the residents.
If the data raise any doubts, then you will prefer to wait a week.