Blue timber H2 is incredibly hard to source, alternative?

Hi Everyone,

I'm currently sourcing the timber materials to frame a double-storey house, brick veneer walls to the ground floor and foam render walls to the first floor.

Apparently, due to timber shortage, I find it's incredibly hard to source the blue timber H2 from multiple suppliers. Does anyone know if we can have an alternative solution for H2 blue timber? E.g. can I use H3 instead? I see plenty of H3 timbers in Bunnings. Reading the AS 1684 Timber Framing Code, it's clearly said the H2 timber is for indoor and H3 is for outdoor. Both are subject to protection from termite and wetting. H3 can protect from leaching. It sounds Ok for me to use H3 as an alternative to H2 timber? What are the consequences of this alternative?

Thanks so much for your help/opinion/advice.

Regards
LT