For the CO2 producer kit, (RJS Malbec with dry skin) I use the following strategy:
1. Before start primary, soak dry skin in 2L water for 1 day with some fresh black fruits (typical Joewine's tweak). And then freeze the mixture. Juice bag was not opened yet. The freezing is to break the cellular wall the skin and fruit to help color and tannin extraction. (Some research says it is effiective)
2. One day before start, defrost the mixture.
3. Prepare 6 gal must with the skin-Fpack mixture in 10L fermenter.
4. To extend the duration of CO2 supply over the duration of EM for EP Amarone (also limited by my bucket volume limit, I have only a 5 gal Home Depot bucket with sealable lid), I pulled out 2 gal of juice with strainer and save it in fridge. Transfer the remaining 4 gal must and all the solids to the 5 gal bucket with gasket lid.
5. Pitch yeast to the 4gal batch and supply CO2 to Fermonster.
6. Plan for about 12 days for this batch and then transfer 3 gal to a 3 gal carboy for secondary.
7. Warm up and add the 2 gal reserve directly on to the left over 1 gal must with lees and skins to continue CO2 production.
8. Hope this can last for another 12 days gas supply.
9. After that rack the wine to a 6 gal carboy and blend with the previous 3 gal batch and finish secondary and subsequent lengthy aging process as usual.
The steps involved for this kit sounds like a semi-EM process. It includes about 24 days of skin contact by feed juice in two steps. Since in the second stage, the 2 gal fresh juice will produce CO2, the risk of oxidation should be low.
Just some crazy ideas. Pretty long process, lots of work. Main purpose is to safeguard the EP batch. If it works, in the future, I will run a cheap one together with an premium kit.