Q.Seedlings
At what point is the right time to start pricking out seedlings for growing on, please?
The time to prick out seedlings can vary with they variety of seeds that you are growing.
A good guideline is when the seedlings have developed at least 2 sets of true leaves.
Here are some articles with tips on seedling care.
https://www.gardeningknowhow.com/garden-how-to/seeds/seedlings-after-germination.htm
https://www.gardeningknowhow.com/garden-how-to/seeds/how-to-harden-off-your-seedlings.htm
https://www.gardeningknowhow.com/garden-how-to/seeds/leggy-seedling.htm