Flanders Red - 1 year old, what to do now?

My Flanders is a year old, and has been sitting on the original yeast cake the whole time. It's quite sour and tart already, but still has a full pellicle. Just wondering what my next step should be. Should I rack it off into another carboy and brew a new batch to pitch onto the yeast cake for blending in a year? Should I just bottle it as is?

Leave it

What is your gravity? My opinion would be to rack it to secondary, rack a fresh wort onto the cake and pitch a fresh pack of roselare. Blend and bottle in a year, but that is just me.

Are you happy with the taste/aroma? And are the gravity readings stable? If yes on both of those, I can't see a reason to not bottle. Or why you would want to blend if you already have a fine product, but that's just me.

I May be wrong but, I don't think it would be a good idea to pitch fresh wort on a year old yeast cake.
How much viable yeast could be left?
Wouldn't it mostly be dead?

I wouldn't do it, but some swear by it. YMMV.

I don't understand why people start out with the idea of blending when making Lambics. Commercial brewers do it due to the variability of the product; they want to make it consistent.

If you have a good reason for blending, then fine, but most people I see just think they should be doing it because that's what the pros do.

I'd just pitch on a part of the cake, to let the Brett grow. Stressing the Brett during it's reproduction phase gives some of it's rustic flavors. If you pitch on a whole cake it will not have to reproduce much. Add some more sacc yeast, as most, if not all the original sacc will have died. Any type will do.

As for your original beer. I'd probably leave it where it is for another 6 months, but there is no issue with racking it or even bottling it.