If the 360 has deleted your recordings and planned recordings it's a sign that the box is faulty, especially if it does it more than once.
You could try a factory reset of the 360, and if you haven't got any recordings you might as well go for the format disk option and if or 'when' the box deletes everything again then try phoning Virgin's bot support which I believe from other posts that's all you get.
The other option is to wait for one of the forum team to respond which might be 2 to 3 day's.
Make sure the Auto delete option is set to off, it probably already is and shouldn't affect planned recordings but you can check by doing the following;
Press Home > Recordings > Recorded > View All > Manage Storage > Enter your pin > Auto delete when space needed > Set to Off.