This was one a bottle that I acquired at auction that came in a mixed lot with things like the Corte 1984 that we had at the Delaforce offline. I didn't enquire what the provenance was.
The port was very interesting. 1 hour's decant produced a port that was really unbalanced, bitter and not very pleasant.
A further hour produced a port that was more mellow, the bitterness had receded and the balance had much improved.
Another hour, and this was showing like a Warre. Lots of sweet plum and a nice, mid-weight balance to it.
The remainder of the bottle is still in the decanter in the wine cabinet, waiting to be drunk either tonight (unlikely given the sunshine and warmth, more likely to finish off the White Port also in the cabinet) or tomorrow night (rain forecast again).