If you paint purely to let stuff out...

[StuffYouCantSay]

What do you do with them afterwards? They aren't suitable for display. They've served their purpose so should probably be chucked. That feels weird and somehow wasteful though. Would you keep them a few days until you're a bit more distanced from then bin them?

I paint on canvas, then paint over in white acrylic to start again!

I have just finished painting on a canvas because I was bored and I suspect if I uploaded it to here I would get told I was very immature 😂 it kept me occupied for the afternoon though and I will just paint over it next week and do something else on it

Take a photograph so you have a record of it.