Private Proxy Switch rotates 20 proxies every 12 hours. If you get the 20 proxies blocked, you will need to wait up to 12 hours and try again. Please care for the proxies and set random page load delays when at all possible. Treat them well and they will treat you well.
However, I've been keeping to run the project with proxy switch until ending, it hasn't raised proxy switch error or blocked, page still can be opened in VWR editor after scraping. see attached log file and full sample data of mine.