OK, so 2027 Perth Bears enter the NRL.
Last year of current TV deal, NRL negotiates-mid contract for a little extra for the 9th game per weekend in that last year - or sells it to an interested new player.
2028 PNG enters the NRL, new 5 year deal starts.
2028-2032 Five years with an odd-sized (19 team) competition. We've been here before in 2002-2006. No problem.
Hopefully the NRL brokers regular games in strategically chosen locations (Adelaide, NZ, Central Queensland, Fiji) to build the following & scope interest.
2028- calls for bids for the 20th team. See what shakes-out
2033 - New TV deal starts. 20th team gets added for a 10th game per week as part of the new contracts, and two of the losing bids tapped as potentially teams 21 & 22 later in the decade - whether there's provision later in this TV deal, or set aside for the next one in circa 2038.