I don't mean to dampen the event, just trying to help.
First I'd never trust reused caps even through a capper.
Get a capper if you wish or use the Grolsch,
I find capping a rather satisfying part of the process.
Seems no one mentioned purging the tap before taking hydrometer readings.
This is most likely where your high reading(s) came from.
It seems wasteful but you really gotta purge a fair bit.
The adjuncts especially can get caught in the tap,
if you take a reading when you make the wort,
the next reading(s) will require less purging.
Also well done on bulk priming on your first go !
good initiative.
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Cheers

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