From looking at the rows of seats I think I've narrowed the total capacity down to around 17,400 (give or take 200).
Bottom tier is 1,960 plus 70 spaces for disabled fans = 2,030.
Middle tier is 490/500, that depends on how many are in the corporate boxes.
Top tier is more difficult to judge because block sizes are not even but it looks to be 2,900.
So stage 1 total capacity is around = 5,430.
We already know the horseshoe is 12,000 capacity.
So total capacity of Home Park at stage 1 is 17,430 +/- 200.
Stage 2 should take it over 20,000.
Bottom tier is 1,960 plus 70 spaces for disabled fans = 2,030.
Middle tier is 490/500, that depends on how many are in the corporate boxes.
Top tier is more difficult to judge because block sizes are not even but it looks to be 2,900.
So stage 1 total capacity is around = 5,430.
We already know the horseshoe is 12,000 capacity.
So total capacity of Home Park at stage 1 is 17,430 +/- 200.
Stage 2 should take it over 20,000.