Yes, there are two interpretations. The rule is ambiguous. There are arguments either way.
The mechanic seems to intend that a long rest can be interrupted. If the consequence of an interpretation is that really, they can't, one might - as I do - feel inclined to question that interpretation. Especially given the implausibility of an hour of combat.
@Phoebasss should know that Crawford has endorsed the version where it does indeed take an hour of combat to interrupt a long rest. The defence is something like - a combination of walking, combat and spell-casting could come to an hour. It comes out about the same - hey, we walked for 59 minutes... better not get in a fight!