Cork Tops and Drying

I kept a bottle of Glinkinche open for over 6 months and the cork dried up. The last opening, the cork disintegrated and many bits of cork ended up in the whisky. No fun!

I currently am storing my Laphroiag bottle on its side to keep the work wet as I plan to keep the bottle for some time. However, the volume will drop to low for whiskey to meet the cork.

Do I need to replace the cork when drinking a bottle over this period of time?

Suggestions welcome.