We know the MC has flashbacks of time with his Dad.
I'd say that the MC was somewhere between 5-8 years old - but this is just a guess on my part.
If we go with the SciFi trope that bad things happen if you meet yourself on another timeline - and if these are true memories, he cannot be with an older version of himself when these memories were made.
Is the MC tied to the person in the mask - I think so.
I just don't know Who this masked person is.
This is one of the good mysteries that keeps the conversation going - part of what I enjoy about Ripples.
Cheers!!