For 2017, we started with 40 senior listed players, 4 Cat. A rookies and Soldo as our Cat. B rookie (40-4-1). Yarran getting the flick early on meant we actually had 39-4-1.
For 2018, we started 40-4-1 with DES as our Cat. B rookie. In reality, we had 38-4-1 as Griffiths and Hampson didn't play and retired early.
For 2019, we started with 38-4-1 post the drafts. It then increased to 38-6-1 with the inclusion of Weller & Stack via the PSS. When Grigg retired it became 37-7-1 with the inclusion of Pickett via the mid-season draft.
For the upcoming 2020, we've filled up our senior list to 38 again. So our current list make-up is 38-5-1 and it's one less in terms of total players than in previous years.
Perhaps it's a TPP issue then? We just don't have the room on our books this year for a sixth Cat. A rookie. DES as a Cat. B rookie isn't included in our salary cap IIRC.