We establish boundary estimates for nonnegative solutions to the
-parabolic equation in
the degenerate range
.
Our main results include new parabolic intrinsic Harnack chains in cylindrical NTA
domains together with sharp boundary decay estimates. If the underlying domain is
-regular,
we establish a relatively complete theory of the boundary behavior, including
boundary Harnack principles and Hölder continuity of the ratios of two
solutions, as well as fine properties of associated boundary measures. There is an
intrinsic waiting-time phenomenon present which plays a fundamental role
throughout the paper. In particular, conditions on these waiting times rule out
well-known examples of explicit solutions violating the boundary Harnack
principle.