I love Affinity Designer as a tool and his pay once license, I'm pretty sure that if you already purchased current version (V2), you will be fine, but I'm afraid they will go the subscription route soon like Adobe and Canva.

Is suspicious that Affinity marketing was always highlighting the pay once license model and against subscription, and in the official announcement there is no mention of that.

A lesson is that with the good ol Inkscape that type of thing that endangered the tool it doesn't happen.