FAST airlock bubbling slowed down to hardly any airlock activity

[Oh mad one]

Hi guys. I'm aiming for a slightly higher ABV fermented turbo grape-apple cider wine. I put in 12 litres of juice and have added half a kilo of brewers sugar. Plus one sachet of Wilko Gervin wine yeast, with a little helping hand from Wilko express yeast compound (which is a combo of yeast plus nutrient). I did this only 3 days ago.

We've been having some very warm weather, and this may have helped to get it kicked off, with a lot of activity. The airlock was bubbling constantly - it even spat out some liquid. It never got slower than one bubble every 2 seconds. Then, as of last night, it slowed down, massively. It's too soon to stop, so I tried to fix this by swirling the tub vigorously in both directions. However, this doesn't appear to have reinvigorated the yeast. Right now, I could sit for minutes next to it waiting for a bubble.

Do you think it's possible the yeast just went crazy eating the simple glucose, and now it has to adapt to the harder work of eating apple and grape fructose? Will it perk up again over the next few days?

 

[Tanglefoot]

Did you take a gravity reading ?
You can't rely on airlock activity to know what's going on, I made an elderflower wine recently that showed no such sign of fermentation but checked with a hydrometer and it was already halfway through the sugars.
After initial burst of activity your yeast is probably just quietly getting on with its thing. Your FV most likely isn't airtight and co2 is escaping round the rim but no worries as most people aren't brewing under pressure and make great beer and wine as has been done for centuries.