May I check practice on first sulphiting of grapes?

[ToulouseLePlot]

Just destemmed and crushed about 90L of merlot.

About 20% of bunches had at least on grape with a white or grey fluffy mould. Some, a few, had about 10% of the grapes 'gone' and the rest inbetween (I guess I would call this a heavily contaminated batch, because if I was at a vineyard I don't think it would be anything like as bad - but these have spent quite some time in a truck from Italy I guess).

I removed the mouldy grapes, but of course squidged the mould all over the bunch. Probably did no more good than just leaving them on.

In the batch with lowest contamination I've put 0.12g/L (3g/25L) K-meta and in the worst one I've put 0.18g/L (4.5g/25L) and I'm leaving 24hrs before innoculating with RC212.

Does that seem right or would you have dosed it with more?

[Cellar_Rat]

Sure does.

Give the yeast, every help you can to get it started - including warming the must up to al least 20c

With mouldy grapes. I always add tannin upto 10g per 25l. This further acts to protect the grapes, will prevent laccase, helping to retain some the proper color.
Do not worry about a high tannic level in the finished wine. It will be used up in the fermentation and if not, can be fined later.