Big deadlines, and big deliveries, no matter the level of planning you do, will always require some extra effort.
There is no way around it, irrespective of the field you are in, that extra push always needs to happen.
You hope for it to be a week, but then a week turns to 2 and then into a month.
This is where your team needs your leadership, your guidance, and your experience to know when 1 turns into 2 that things are going to change, that you might need to pump the brakes, that you might have to set rest nights/days aside, that instead of everyone being separate, the team does it together.
There are many things you can do to mitigate and manage burnout when you’re in – the key is to not turn a blind eye to it, as soon as the first extra hours start – you’re watching, and you don’t stop watching until it’s done.
And the last person to be putting in the extra time is you.
You signed up for this, not your team.