Recurring payments, coupons, and pricing increases

I’m planning to offer very low introductory pricing to encourage businesses to get on board even though my site doesn’t have much traffic yet.
I have recurring payments and coupons set up to offer discount for all future payments (Paypal and Stripe).

Questions:
1) If I increase the package prices when my site traffic is heavier, I’m assuming that neither PayPal nor Stripe will have a way of knowing that the price has changed and pre-existing recurring payments will continue unchanged—correct?

2) If my assumtion is incorrect and GD can somehow notify Paypal or Stripe that the recuring price has increased, will coupons stay active and apply the discount on the new rate?

I need to know how this will work so I know how to word my promo materials (ie. “Lock in your early-bird rate for life”, or “Lifetime 25% discount if you sign up now” etc.