Mould / tool conditioning prior to use (polyester)

I have read a lot about the need to condition polyester moulds before using them in production. Often taking light layup pulls after waxing and PVA'ing.
My experience suggests that problems occur when a mould/tool is new and continues to produce styrene for several weeks. I have had good results with complex shape polyester moulds when allowed to fully cure before applying release wax.
I would like to understand the mechanics / chemistry of polyester mould "conditioning" and possibly endorse my experiences.
I can certainly testify to bad release from new moulds, despite numerous waxes.
We have made epoxy Transpac 52 yachts and they appear to be ok immediately after application of chemical release agents with subsequent application of epoxy carbon pre-pregs. I assume this is because there are no styrene emmisions from epoxy tooling.
Look forward to any info.
Richard