All these stories lead me to wonder why BA is so undisciplined with giving compensation under circumstances that ought not be compensated contractually/legally, and whether they could have been putting that money into services that otherwise were cut over the years...
In this case an evening flight from LHR to INV would help the OP no end. Am sure Scotrail pre pandemic used to have an 20.30 service to INV too.
Funnily enough KL do have a 21.35 flight ex AMS which lands at INV at 22.15.