Hi Jonathan,
Glad the payment link is working now.
About the upgrade: our billing doesn't do mid-cycle proration, but you don't lose anything by upgrading before August 10 — the credits from your current plan stay in your account and remain usable for 12 months from the date they were purchased, even after the plan change. So the amount you've already paid for this cycle isn't wasted; those credits simply stack on top of the new plan's credits, which are available immediately.
So you have two options:
1. Upgrade now — you pay the full price of the new plan today, get its credits right away, and keep your current remaining credits on top (valid for 12 months).
2. Wait until August 10 — let the current cycle finish and switch then, so there's no overlap at all.
If you don't need the extra credits urgently, option 2 is the simplest. If you do, option 1 doesn't cost you anything extra in practice — it just moves your renewal date forward.
Let me know which one you prefer and I'll help you through it.