Some recent rumours are related to Messi's possible departure this summer. As you know he hasn't decided to extend his contract with PSG yet. The team has actually had intentions to go on with him for at least one more year. But it looks like he wants to evaluate his options first. He is familiar with this free agent situation you know so it wouldn't be a problem for him. He must have some priorities for himself now.
And honestly one of these must be to sign back for Barcelona. Nearly his whole career has passed with Barcelona in the end so I understand him about thinking emotional. There hasn't been such thing like he couldn't adapt to this environment. On the contrary, he has been one of the most performing players of PSG. But PSG must also know that this day would come.
In case of a Messi comeback, Barcelona would be much stronger by the start of next season.
To base my statement on this assertion, it means that his transfer back to Barcelona is very much possible because Messi considers Camp Nou as his home. It will be a welcome home show and automatically he will become the king he was.
It doesn't matter where he comes from; his heart truly belongs to the Blaugrana. Camp Nou still cherishes him, and it's no surprise why. To be honest he has achieved more than any other player in history. Certainly Messi will accept Barcelona's offer and return home because his love for this club than anything else. Both Messi and Barcelona need each other for their system to work. I believe that the Barca board would want to keep everything secret until the final confirmation.