The RNHF had a Harvard III at RNAS Lee-on-Solent during the 1980s, but it was very reclusive. It was mothballed and sold at auction to raise funds in 1994, like their gorgeous Tiger Moth.
I presume it was the BBMF that flew over Eastleigh at 1730.
Nipped out to spot at least one Spitfire, plus another or a Hurricane in the distance.
A rumble went over shortly before those two, which could have been the Lanc.