On 2 March, Bitdefender VPN removed about 30-40 lines of entries in my Windows 11 Hosts file. I've run VPN for six months and not previously seen this issue. I use Hosts for my development, monitoring, and related tasks to avoid split DNS inside my network. Prior yesterday, VPN added its entries at the bottom of Hosts. Yesterday, it wiped everything above those entries.
Unfortunately, I have no artifacts or logs, as I did not recognize initially that the Hosts file was the problem, and I uninstalled the VPN during troubleshooting. I removed it completely (with Revo Uninstaller) because I also have a subscription to NETGEAR Armor, and there is some overlap in products, and I wasn't sure what app was causing the issue.
Fortunately, I have a relatively recent copy to restore, but you might want to look at the code that manipulates the Hosts file and ensure it never removes any entries.