David J Bush typed

An Oyster card sounds like an excellent idea. But I already bought a
"London Pass" which provides free use throughout zones 1-6 plus access
to a bunch of touristy stuff. I'll probably have to scramble around like
a madman to get my money's worth on that.

If your pass covers Zones 1-6, you should not need to buy any other
ticket to cover your journey from Heathrow, which is in Zone 6 (so long
as it's valid on your arrival date). You won't need an Oyster, then.

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Helen D. Vecht:
Edgware.