They are unlocked and available to be completed now. Unlike a Dockyard event, or the Novorossiysk event which had a time-delay lock between stages.
A player mathed out that you would have 6 days after attaining the Repulse in a free-to-play manner to work your way through all the tasks. That's... not a small ask from what I'm seeing. It's doable, but it doesn't look very fun.
That being said, if a player purchased some stages so they could grind out the Marlborough, then the Repulse unlocks faster and the time allotted is around 15 days, which is a significant difference.
They are all available and not Time Locked in a strict sense.
They are locked behind the Repulse. While that's a timed access ship for a Free-to-Play style, it's available early for those who wish to spend Doubloons on the Dockyard.
The descriptions read accurately, but I can understand the annoyance on the "technicalities" of the situation
Thanks for the ping. Hope I helped clear things up~