Many things can interfere with satellite - Television is a great example (dishes go in and out all the time while cable usually doesn't because it's a hard line, similar to cordless telephones instead of land lines).
The VPN will drop her because its connection was dropped. It's not going to keep it open when the physically connection is down.
This from HUGHESNET:
Disadvantages of Broadband by Satellite
Line of Sight
In order for a satellite dish to receive a broadband internet signal, it must have a free line of sight to the geostationary satellite in orbit. Obstacles such as buildings, trees, and even leaves can get the way of line-of-sight and block the signal, leaving you with no connection.
Weather
Although rain will not block a broadband by satellite signal, it will cause an interference known as "rain fade." Rain fade results in slower upload & download speeds and a patchy connection.
Connection Speed
When an internet signal has to travel 22,000 miles to a satellite in earth's orbit and back, a certain about of latency (the delay between requesting some data and getting a response) is unavoidable. The average latency for broadband by satellite is between 500 and 900 milliseconds-much worse than even a dial-up internet connection, where the latency is only 150 to 200 milliseconds. Although this slow data transfer speed is just fine for basic internet usage-email and web browsing-it is too slow for computer applications that require real-time internet access, such as internet gaming, videoconferencing, and VoIP (Voice over IP) telephone conversations.
