It also always depends a bit on the strain or the pheno.
In your case, I would give them another 1-2 weeks and then switch.
Some stretch more, some less, and then it depends on what your setup can handle.
If you notice they are stretching too much, give them a bit more light as long as they look healthy.
If you want more stretch, give them a bit less light.
You can calculate the DLI (daily light integral) yourself.
Especially with LEDs, it's important to get familiar with stuff like this.
Good luck, they look great ✌️