Those bases are heavily defended against drones. Ukraine has tried repeatedly to hit these bases and only succeeded once prior hitting a single TU-95. Since the

Those bases are heavily defended against drones. Ukraine has tried repeatedly to hit these bases and only succeeded once prior hitting a single TU-95. Since then there's been nothing as Russia adapted. The long range drones required have a larger radar signature and Pantsir + AA guns on the ground are pretty good at stopping that. That plus heavy EW and GPS jamming. Which is why Ukraine spent the last year hitting softer targets like oil and factories.