All clubs have to nominate every season what division they want to play in, so every club has the ability to request to go down already. This is nothing new.
The only difference is the straight promotion/relegation swap will not occur now.
Even in the past we've seen premiers not go up (ie argenton folding) or additional teams going down (Terrace most recently) and then teams apply to be promoted.
I've been through the process and been promoted twice despite not being premiers.

The lack of stability of clubs in the region is a bigger concern imo. Clubs get promoted and can't sustain it beyond 2 or 3 seasons. As above, teams fold and withdraw too much. Even Uni had to amalgamate from two into one division in recent times.
Look at ZPL from the last 5 years. Uni, Terrace, Morisset, Jesmond, have all fallen by the wayside. Bero would struggle in ZL2 based on the past few seasons. This should be our strongest clubs competing in our 'Premier' competition.
I know volunteers are a big part, and players move etc, but it's a worry that 'strong' clubs can be crippled so easily in the space of a few years.