BRP Collection Timelines

Hello everyone. I understand that upon entering the UK, a BRP will be issued and sent to the nearest post-office. My question is about the timelines for BRP collection.

I plan to travel in August and want to understand how many days upon my arrival the BRP will be ready for pickup. E.g if I arrive the UK on the 9th of August, what is the usual wait time before the BRP arrives at the post-office?

Thank you.