We know physical examples of nontrivial bundles in field theory where the base manifold is spacetime. For example in electromagnetism Dirac monopole is an example of a nontrivial vector bundle $A_{\mu}$ over spacetime. On the other hand in particle mechanics the base manifold is just a one dimensional manifold parametrized by time $t$. Let’s call this 1-dimensional manifold as the time manifold in contrast with the spacetime manifold.
Now my question is, do you know examples of physical systems with nontrivial bundles over time manifold, as $\mathbb{R}$, or even compactified as a circle $S^1$?