Sad news - saw mention of his passing too in JazzWax.
Remember seeing him several times with Ronnie Scott's Quintet at the Scott club, also with his own trio at the club. The Scott quintet was the lineup which immediately preceded the one with Dick Pearce in the front line I think. Always thought that, like Scott, he was hugely under-rated.
Tubby Hayes certainly knew his worth - will dig out the 'Rumpus' CD on Savage Solveig in recognition. RIP.
Here's 'Inner Splurge' with the Hayes Orchestra - Stewart solos superbly at around 4.5 minutes in.
Inner Splurge