When does isolation end?

[Ohtherewearethen]

My husband has been diagnosed with covid so we both have to isolate. We received notice from the NHS that isolation will end on Friday. We have to isolate until Friday. One of us thinks that this includes Friday, so can't go out until Saturday, and the other thinks this means we can go out on Friday. Who do you think is correct please?
YABU - isolation ends Friday. You can go out on Friday
YANBU - isolation includes Friday. You can't go out until Saturday.

You can go out on Saturday, isolation will end at midnight

Saturday.

The last day of isolation is Friday. You can mix again on Saturday.

We have a case of covid in our household and NHS track and trace were very specific in saying that it was up until midnight on the last day. So for you, it will mean you can mix on Saturday.