[Sasquachulator]

So ive got a set of 4 Bridgestone Potenza summer runflats sitting my garage.
They are the OEM tire from our 2017 BMW X1.

When we got the car in 2017, we were only a couple months way from the winter season so we needed to switch them out for something that actually works in the snow, and we've since swapped them out for some Continental DWS06 all seasons.

The plan was to use the Contis all season long until the winter traction becomes no good, then get a dedicated set of winter tires. We'd continue using the Contis for summer only until its time to replace them, in which case we'll just equip the Bridgestones since we have them available.

Well 7 years later and 76,000kms or so later, (We got it new, and it was our only car for about 2 years at first before we got a second car which means its usage started getting split with the second car) the Conti's still have life (the DWS indicator (Dry, Wet, Snow, the letters wear out over time indicating they are no longer usable for that road condition....S goes first, then W then D) still has the S intact) and we may instead just replace them eventually with an all weather tire (or at least replace them with the same or equivalent all seasons that actually works good in snow/ice) and not have to deal with the seasonal tire swap.

Kind of brings me back to the Bridgestone's. they've just been sitting in the same spot in my unheated garage this whole time (4 stacked on top of each other, individually wrapped in plastic bags but not sealed air tight...(just tied the end of the bags) and i started thinking about just selling them. With them being so old and unused it has come to my attention that these might potentially be bad now so i may not be able to sell them. Might have to just discard them.

My question is...anyone know what the general shelf life of unused tires are?
I've read about 5-6 years, perhaps more in ideal storage conditions.