Rogue plate voltage

Anyone know what the plate voltage is on a Rogue Mag 99 preamp? I'm curious to know if I can expect reasonable life out of 5692 tubes. Thanks in advance.
For those that visited and for other Rogue Mag99 owners, Mark O'Brien has informed me that the 5692 tube is OK to use. Also he said that the plate to cathode voltage is less than 100V. So there.