The 428 is the number of albums on the curated list presented by Tidal. Your assumption is correct - the total is a lot more as evidenced by the excel list. I may have missed it, but I don’t think bulk import has been discussed.

NC1: 861v4+ID40, 218, 251(to outdoors), DSP8000SE (upgraded). 5500VC, 5500s, DirecTV, Oppo BD103, QNAP251, Roon
NC2-see FL 2 with Triad Silver Speakers and Acurus Amps

FL1: G61R, 218, DSP8000SEs, 5500HC, DSP5000s, DirecTv, Oppo BD103, QNAP469, Roon
FL2: Marantz 7005, M60s, M60C, M33s, Oppo BDP-93, MS200, Roon