It seems that the debug skeletal mesh in the anim blueprint preview can end up playing the incorrect anim sequences. This happens when a sequence player, with the anim sequence specified via property access, is connected directly to the output of the graph. If that sequence player is switched for another that has the anim sequence specified directly via the sequence property on the node, after compiling the blueprint, the previous anim sequence continues to play. Closing and reopening the anim blueprint editor resolves the issue.