Full agree with Marc answer. Obviously you should check what is doing the concurrence or similar products on the market but I guess that you already did it..
My advice is to give grace period of 1-3 months to the current userbase and give them some invite vouchers and make the new subscribers pay (start low as Marc said so they never feel overpaid). Then you'll gather enough metrics to adjust your pricing strategy accordingly without it impacting your userbase (actually some are gonna love you for making them feel special early birds who don't have to pay at the beginning).
Full agree with Marc answer. Obviously you should check what is doing the concurrence or similar products on the market but I guess that you already did it..
My advice is to give grace period of 1-3 months to the current userbase and give them some invite vouchers and make the new subscribers pay (start low as Marc said so they never feel overpaid). Then you'll gather enough metrics to adjust your pricing strategy accordingly without it impacting your userbase (actually some are gonna love you for making them feel special early birds who don't have to pay at the beginning).