Short answer is yes - sort of.
First understand the biggest outlier is 5 watt mode. I know only one tube is running to output power, the other are in standby. Unless you are driving the tube significantly harder, the tube life will be comparable, but one tube will wear quicker. I switch positions every 6 months to ensure ever wear. I get 2-3 years on my tubes, because that's when I change them.
The tubes in 15 W and 25 W modes should wear about equal as they are both used.
I tend to pick 5W to drive it harder at lower volumes so it tends to wear the tube quicker.
It really comes down to how hard you drive the power section (and which tubes) in each mode.