The highest gravity beers I have done were 9-10% ABV, so not quite as high as yours.
However, I have never had to reseed, but one thing I do out of greed rather than good technique is to transfer the less floculant yeast into the bottling bucket and make sure they all get well mixed with the priming sugar (liquid).
It could be completely anectdotal, but to me I think it is these yeasts that you need to carbonate, not the flocced ones that have built their reserves and gone to sleep. You are trying to wake them up in a very toxic environment to work on a scarce food source.
Have you thought about reseeding with a yeast designed for bottle carbonation?
I am not sure if you can get it, and there may be equivalents in each country, but one that springs to mind is Safbrew F-2.
To quote Joshua - JMHO, YMMV
Post #76 made 8 years ago
G B
I spent lots of money on booze, birds and fast cars. The rest I squandered
I've stopped drinking, but only when I'm asleep
I ONCE gave up women and alcohol - it was the worst 20 minutes of my life
I spent lots of money on booze, birds and fast cars. The rest I squandered
I've stopped drinking, but only when I'm asleep
I ONCE gave up women and alcohol - it was the worst 20 minutes of my life
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