Clearly they’re making it so Y4 will end with everyone at 1000 power and then we’ll get the next big drop; which will either be another year of seasons plus a shadowkeep-esque campaign expansion — or D3, which will be dependent on the success of Y4. Should also note the timing of this with the arrival of the Veil and the reveal of Savathûn. I doubt these will be in the same release.