Currently you can only drip Modules, not the lessons within them, you can only lock them and require that someone completes another lesson or module before it's available. Many coaches I work with want to drip content on a weekly basis but don't want separate modules for each week as their framework might be pillars or themes. This is very common for coaches who are delivering a product that has a specific duration.

For example:

Someone buys a 10 week program. They get access right away to the welcome and intro module and then Pillar 1: Week 1.

After 7 days they would get access to Week 2.

Then after another 7 days Pillar 2 and Week 3 opens

Etc.

The weeks open up regardless of where they are, so if the "student" get behind, that's on them.