My mother has unplugged the two PCs where I had the nodes

[Alexey]

You can run nodes unless you have lost data. In the last case they will be disqualified pretty quick.
The disqualification for downtime is currently under development:

Blueprint: tracking downtime with audits

Hey everyone, we have a new design here for tracking downtime with audits We had a previous discussion on a related document here Blueprint: Downtime Disqualification , but we decided to reconsider using audits to measure storage node downtime. Let us know what you think