Assuming usage as a mountain bike, an air spring suspension fork on a hardtail is to be maintained every 50 hours of riding.
By comparison it's sufficient, and plenty reasonable, to replace a chain ridden in a clean environment, regularly run through a scrubber and lubricated, after some specific wear (0.5% stretch) is reached, rather than after some riding time or riding distance—even if that stretch is reached after 10,000 or 15,000 km rather than 2,000 or 3,000 km.
For a hardtail ridden more often on snow/ice-covered roads with the suspension locked than on trails with the suspension unlocked, is there a wear indication that will determine when it's time for maintenance or overhaul—an indication that skips the 50-hour recommendation?
Motivation
The motivation for the question is this: riding at a minimum three times a week, the first two for two hours each and the third for four hours, means reaching 50 hours after six weeks.
Now suppose that this is one maintenance task I’m shying away from doing myself (because, as with bleeding hydraulic brakes, I don’t want to find a puddle of oil on my indoor floor—nor do I want to discover what brake/suspension fluids do to the lacquer), does that mean I should go back to the shop every six weeks seeking maintenance (or can I lock out the fork when I either don’t need or want suspension, and extend this interval by relying on some test)?